C# Delegates and Events MCQ Questions with Answers – Page 2 (Latest 2026)

Q51. Which statement about WeakEventManager is most accurate?

A. A logging system. B. A delegate type. C. A type of GC. D. Helps avoid memory leaks via weak event subscriptions.

Select an answer to check.

Answer: Helps avoid memory leaks via weak event subscriptions.

Here, Helps avoid memory leaks via weak event subscriptions. is the right choice. Prevents publisher-keeps-subscriber-alive issues. It aligns directly with what the question asks about which statement about weakeventmanager is most accurate. Competing choices sound plausible, but they miss the key condition.

Q52. How is WeakEventManager best characterized?

A. A delegate type. B. A logging system. C. A type of GC. D. Helps avoid memory leaks via weak event subscriptions.

Select an answer to check.

Answer: Helps avoid memory leaks via weak event subscriptions.

In this case, Helps avoid memory leaks via weak event subscriptions. is correct. Prevents publisher-keeps-subscriber-alive issues. It aligns directly with what the question asks about how is weakeventmanager best characterized. Competing choices sound plausible, but they miss the key condition.

Q53. Which option best describes event invocation pattern in C#/.NET?

A. handler?.Invoke(this, e) to handle null safely. B. Always invoking without null check. C. Pure assignment. D. Using delegate(){}.

Select an answer to check.

Answer: handler?.Invoke(this, e) to handle null safely.

The best option here is handler?.Invoke(this, e) to handle null safely.. Idiomatic null-safe invoke. It aligns directly with what the question asks about which option best describes event invocation pattern in. Competing choices sound plausible, but they miss the key condition.

Q54. What is the primary purpose of event invocation pattern?

A. Using delegate(){}. B. Always invoking without null check. C. Pure assignment. D. handler?.Invoke(this, e) to handle null safely.

Select an answer to check.

Answer: handler?.Invoke(this, e) to handle null safely.

For this question, handler?.Invoke(this, e) to handle null safely. is correct. Idiomatic null-safe invoke. It aligns directly with what the question asks about what is the primary purpose of event invocation. Competing choices sound plausible, but they miss the key condition.

Q55. Which statement about event invocation pattern is most accurate?

A. Using delegate(){}. B. Always invoking without null check. C. handler?.Invoke(this, e) to handle null safely. D. Pure assignment.

Select an answer to check.

Answer: handler?.Invoke(this, e) to handle null safely.

handler?.Invoke(this, e) to handle null safely. is the correct answer here. Idiomatic null-safe invoke. It aligns directly with what the question asks about which statement about event invocation pattern is most. Competing choices sound plausible, but they miss the key condition.

Q56. How is event invocation pattern best characterized?

A. Pure assignment. B. Using delegate(){}. C. Always invoking without null check. D. handler?.Invoke(this, e) to handle null safely.

Select an answer to check.

Answer: handler?.Invoke(this, e) to handle null safely.

Here, handler?.Invoke(this, e) to handle null safely. is the right choice. Idiomatic null-safe invoke. This matches the core idea being tested around how is event invocation pattern best characterized. Competing choices sound plausible, but they miss the key condition.

Q57. Which option best describes EventArgs in C#/.NET?

A. An interface. B. A delegate. C. An attribute. D. Base class for event payloads.

Select an answer to check.

Answer: Base class for event payloads.

In this case, Base class for event payloads. is correct. Subclass for custom data. This matches the core idea being tested around which option best describes eventargs in c#/.net. Competing choices sound plausible, but they miss the key condition.

Q58. What is the primary purpose of EventArgs?

A. Base class for event payloads. B. An interface. C. An attribute. D. A delegate.

Select an answer to check.

Answer: Base class for event payloads.

The best option here is Base class for event payloads.. Subclass for custom data. This matches the core idea being tested around what is the primary purpose of eventargs. Competing choices sound plausible, but they miss the key condition.

Q59. Which statement about EventArgs is most accurate?

A. Base class for event payloads. B. An attribute. C. An interface. D. A delegate.

Select an answer to check.

Answer: Base class for event payloads.

For this question, Base class for event payloads. is correct. Subclass for custom data. This matches the core idea being tested around which statement about eventargs is most accurate. Competing choices sound plausible, but they miss the key condition.

Q60. How is EventArgs best characterized?

A. A delegate. B. An interface. C. An attribute. D. Base class for event payloads.

Select an answer to check.

Answer: Base class for event payloads.

Base class for event payloads. is the correct answer here. Subclass for custom data. This matches the core idea being tested around how is eventargs best characterized. Competing choices sound plausible, but they miss the key condition.

Q61. Which option best describes a custom EventArgs in C#/.NET?

A. Inherits EventArgs and adds typed properties. B. A class implementing IEvent. C. A static class. D. A struct only.

Select an answer to check.

Answer: Inherits EventArgs and adds typed properties.

Here, Inherits EventArgs and adds typed properties. is the right choice. Carries event-specific data. That is exactly the concept behind which option best describes a custom eventargs in in this context. Competing choices sound plausible, but they miss the key condition.

Q62. What is the primary purpose of a custom EventArgs?

A. A static class. B. A struct only. C. Inherits EventArgs and adds typed properties. D. A class implementing IEvent.

Select an answer to check.

Answer: Inherits EventArgs and adds typed properties.

In this case, Inherits EventArgs and adds typed properties. is correct. Carries event-specific data. That is exactly the concept behind what is the primary purpose of a custom in this context. Competing choices sound plausible, but they miss the key condition.

Q63. Which statement about a custom EventArgs is most accurate?

A. A struct only. B. A static class. C. A class implementing IEvent. D. Inherits EventArgs and adds typed properties.

Select an answer to check.

Answer: Inherits EventArgs and adds typed properties.

The best option here is Inherits EventArgs and adds typed properties.. Carries event-specific data. That is exactly the concept behind which statement about a custom eventargs is most in this context. Competing choices sound plausible, but they miss the key condition.

Q64. How is a custom EventArgs best characterized?

A. Inherits EventArgs and adds typed properties. B. A class implementing IEvent. C. A static class. D. A struct only.

Select an answer to check.

Answer: Inherits EventArgs and adds typed properties.

For this question, Inherits EventArgs and adds typed properties. is correct. Carries event-specific data. That is exactly the concept behind how is a custom eventargs best characterized in this context. Competing choices sound plausible, but they miss the key condition.

Q65. Which option best describes delegate inference in C#/.NET?

A. Compiler infers delegate type from method group. B. Always requires explicit cast. C. A reflection-only feature. D. A runtime-only feature.

Select an answer to check.

Answer: Compiler infers delegate type from method group.

Compiler infers delegate type from method group. is the correct answer here. Simplifies code. That is exactly the concept behind which option best describes delegate inference in c#/.net in this context. Competing choices sound plausible, but they miss the key condition.

Q66. What is the primary purpose of delegate inference?

A. Always requires explicit cast. B. Compiler infers delegate type from method group. C. A runtime-only feature. D. A reflection-only feature.

Select an answer to check.

Answer: Compiler infers delegate type from method group.

Here, Compiler infers delegate type from method group. is the right choice. Simplifies code. It fits the requirement in the prompt about what is the primary purpose of delegate inference. Competing choices sound plausible, but they miss the key condition.

Q67. Which statement about delegate inference is most accurate?

A. A runtime-only feature. B. Always requires explicit cast. C. Compiler infers delegate type from method group. D. A reflection-only feature.

Select an answer to check.

Answer: Compiler infers delegate type from method group.

In this case, Compiler infers delegate type from method group. is correct. Simplifies code. It fits the requirement in the prompt about which statement about delegate inference is most accurate. Competing choices sound plausible, but they miss the key condition.

Q68. How is delegate inference best characterized?

A. Always requires explicit cast. B. Compiler infers delegate type from method group. C. A reflection-only feature. D. A runtime-only feature.

Select an answer to check.

Answer: Compiler infers delegate type from method group.

The best option here is Compiler infers delegate type from method group.. Simplifies code. It fits the requirement in the prompt about how is delegate inference best characterized. Competing choices sound plausible, but they miss the key condition.

Q69. Which option best describes closure capture in C#/.NET?

A. Captured by hash. B. Lambdas capture surrounding variables by reference. C. Always by value. D. Always by reference of name only.

Select an answer to check.

Answer: Lambdas capture surrounding variables by reference.

For this question, Lambdas capture surrounding variables by reference. is correct. Beware modification semantics. It fits the requirement in the prompt about which option best describes closure capture in c#/.net. Competing choices sound plausible, but they miss the key condition.

Q70. What is the primary purpose of closure capture?

A. Always by reference of name only. B. Lambdas capture surrounding variables by reference. C. Captured by hash. D. Always by value.

Select an answer to check.

Answer: Lambdas capture surrounding variables by reference.

Lambdas capture surrounding variables by reference. is the correct answer here. Beware modification semantics. It fits the requirement in the prompt about what is the primary purpose of closure capture. Competing choices sound plausible, but they miss the key condition.

Q71. Which statement about closure capture is most accurate?

A. Captured by hash. B. Lambdas capture surrounding variables by reference. C. Always by value. D. Always by reference of name only.

Select an answer to check.

Answer: Lambdas capture surrounding variables by reference.

Here, Lambdas capture surrounding variables by reference. is the right choice. Beware modification semantics. This is the most accurate statement for which statement about closure capture is most accurate. Competing choices sound plausible, but they miss the key condition.

Q72. How is closure capture best characterized?

A. Lambdas capture surrounding variables by reference. B. Always by reference of name only. C. Captured by hash. D. Always by value.

Select an answer to check.

Answer: Lambdas capture surrounding variables by reference.

In this case, Lambdas capture surrounding variables by reference. is correct. Beware modification semantics. This is the most accurate statement for how is closure capture best characterized. Competing choices sound plausible, but they miss the key condition.

Q73. Which option best describes delegate combination in C#/.NET?

A. Replaces handlers. B. operator + concatenates delegate invocation lists. C. Disables invocation. D. Removes handlers.

Select an answer to check.

Answer: operator + concatenates delegate invocation lists.

The best option here is operator + concatenates delegate invocation lists.. Foundation of multicast. This is the most accurate statement for which option best describes delegate combination in c#/.net. Competing choices sound plausible, but they miss the key condition.

Q74. What is the primary purpose of delegate combination?

A. Disables invocation. B. operator + concatenates delegate invocation lists. C. Removes handlers. D. Replaces handlers.

Select an answer to check.

Answer: operator + concatenates delegate invocation lists.

For this question, operator + concatenates delegate invocation lists. is correct. Foundation of multicast. This is the most accurate statement for what is the primary purpose of delegate combination. Competing choices sound plausible, but they miss the key condition.

Q75. Which statement about delegate combination is most accurate?

A. Disables invocation. B. operator + concatenates delegate invocation lists. C. Replaces handlers. D. Removes handlers.

Select an answer to check.

Answer: operator + concatenates delegate invocation lists.

operator + concatenates delegate invocation lists. is the correct answer here. Foundation of multicast. This is the most accurate statement for which statement about delegate combination is most accurate. Competing choices sound plausible, but they miss the key condition.

Q76. How is delegate combination best characterized?

A. Removes handlers. B. Disables invocation. C. operator + concatenates delegate invocation lists. D. Replaces handlers.

Select an answer to check.

Answer: operator + concatenates delegate invocation lists.

Here, operator + concatenates delegate invocation lists. is the right choice. Foundation of multicast. It aligns directly with what the question asks about how is delegate combination best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q77. Which option best describes delegate removal in C#/.NET?

A. Replaces all handlers. B. Throws if missing. C. operator - removes a method from invocation list. D. Adds another method.

Select an answer to check.

Answer: operator - removes a method from invocation list.

In this case, operator - removes a method from invocation list. is correct. Idempotent if not present. It aligns directly with what the question asks about which option best describes delegate removal in c#/.net. The remaining choices fail because they don’t satisfy the full definition.

Q78. What is the primary purpose of delegate removal?

A. Replaces all handlers. B. Throws if missing. C. Adds another method. D. operator - removes a method from invocation list.

Select an answer to check.

Answer: operator - removes a method from invocation list.

The best option here is operator - removes a method from invocation list.. Idempotent if not present. It aligns directly with what the question asks about what is the primary purpose of delegate removal. The remaining choices fail because they don’t satisfy the full definition.

Q79. Which statement about delegate removal is most accurate?

A. operator - removes a method from invocation list. B. Adds another method. C. Replaces all handlers. D. Throws if missing.

Select an answer to check.

Answer: operator - removes a method from invocation list.

For this question, operator - removes a method from invocation list. is correct. Idempotent if not present. It aligns directly with what the question asks about which statement about delegate removal is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q80. How is delegate removal best characterized?

A. Adds another method. B. operator - removes a method from invocation list. C. Throws if missing. D. Replaces all handlers.

Select an answer to check.

Answer: operator - removes a method from invocation list.

operator - removes a method from invocation list. is the correct answer here. Idempotent if not present. It aligns directly with what the question asks about how is delegate removal best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q81. Which option best describes Func chaining in C#/.NET?

A. Static class only. B. Always sequential await. C. Reflection only. D. Composing functions via delegates.

Select an answer to check.

Answer: Composing functions via delegates.

Here, Composing functions via delegates. is the right choice. Encourages function composition. This matches the core idea being tested around which option best describes func chaining in c#/.net. The remaining choices fail because they don’t satisfy the full definition.

Q82. What is the primary purpose of Func chaining?

A. Reflection only. B. Static class only. C. Composing functions via delegates. D. Always sequential await.

Select an answer to check.

Answer: Composing functions via delegates.

In this case, Composing functions via delegates. is correct. Encourages function composition. This matches the core idea being tested around what is the primary purpose of func chaining. The remaining choices fail because they don’t satisfy the full definition.

Q83. Which statement about Func chaining is most accurate?

A. Always sequential await. B. Reflection only. C. Static class only. D. Composing functions via delegates.

Select an answer to check.

Answer: Composing functions via delegates.

The best option here is Composing functions via delegates.. Encourages function composition. This matches the core idea being tested around which statement about func chaining is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q84. How is Func chaining best characterized?

A. Static class only. B. Composing functions via delegates. C. Reflection only. D. Always sequential await.

Select an answer to check.

Answer: Composing functions via delegates.

For this question, Composing functions via delegates. is correct. Encourages function composition. This matches the core idea being tested around how is func chaining best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q85. Which option best describes eventing across threads in C#/.NET?

A. Skip threading concerns. B. Marshal handlers to UI thread via context. C. Always invoke on caller thread. D. Always raise from UI only.

Select an answer to check.

Answer: Marshal handlers to UI thread via context.

Marshal handlers to UI thread via context. is the correct answer here. Important for UI apps. This matches the core idea being tested around which option best describes eventing across threads in. The remaining choices fail because they don’t satisfy the full definition.

Q86. What is the primary purpose of eventing across threads?

A. Always raise from UI only. B. Skip threading concerns. C. Always invoke on caller thread. D. Marshal handlers to UI thread via context.

Select an answer to check.

Answer: Marshal handlers to UI thread via context.

Here, Marshal handlers to UI thread via context. is the right choice. Important for UI apps. That is exactly the concept behind what is the primary purpose of eventing across in this context. The remaining choices fail because they don’t satisfy the full definition.

Q87. Which statement about eventing across threads is most accurate?

A. Always invoke on caller thread. B. Marshal handlers to UI thread via context. C. Skip threading concerns. D. Always raise from UI only.

Select an answer to check.

Answer: Marshal handlers to UI thread via context.

In this case, Marshal handlers to UI thread via context. is correct. Important for UI apps. That is exactly the concept behind which statement about eventing across threads is most in this context. The remaining choices fail because they don’t satisfy the full definition.

Q88. How is eventing across threads best characterized?

A. Always invoke on caller thread. B. Skip threading concerns. C. Marshal handlers to UI thread via context. D. Always raise from UI only.

Select an answer to check.

Answer: Marshal handlers to UI thread via context.

The best option here is Marshal handlers to UI thread via context.. Important for UI apps. That is exactly the concept behind how is eventing across threads best characterized in this context. The remaining choices fail because they don’t satisfy the full definition.

Q89. Which option best describes event memory leaks in C#/.NET?

A. Forgetting to unsubscribe keeps subscribers alive. B. No leaks possible. C. Leaks only with structs. D. GC always cleans them.

Select an answer to check.

Answer: Forgetting to unsubscribe keeps subscribers alive.

For this question, Forgetting to unsubscribe keeps subscribers alive. is correct. Unsubscribe in Dispose. That is exactly the concept behind which option best describes event memory leaks in in this context. The remaining choices fail because they don’t satisfy the full definition.

Q90. What is the primary purpose of event memory leaks?

A. Leaks only with structs. B. No leaks possible. C. Forgetting to unsubscribe keeps subscribers alive. D. GC always cleans them.

Select an answer to check.

Answer: Forgetting to unsubscribe keeps subscribers alive.

Forgetting to unsubscribe keeps subscribers alive. is the correct answer here. Unsubscribe in Dispose. That is exactly the concept behind what is the primary purpose of event memory in this context. The remaining choices fail because they don’t satisfy the full definition.

Q91. Which statement about event memory leaks is most accurate?

A. GC always cleans them. B. Leaks only with structs. C. Forgetting to unsubscribe keeps subscribers alive. D. No leaks possible.

Select an answer to check.

Answer: Forgetting to unsubscribe keeps subscribers alive.

Here, Forgetting to unsubscribe keeps subscribers alive. is the right choice. Unsubscribe in Dispose. It fits the requirement in the prompt about which statement about event memory leaks is most. The remaining choices fail because they don’t satisfy the full definition.

Q92. How is event memory leaks best characterized?

A. No leaks possible. B. GC always cleans them. C. Forgetting to unsubscribe keeps subscribers alive. D. Leaks only with structs.

Select an answer to check.

Answer: Forgetting to unsubscribe keeps subscribers alive.

In this case, Forgetting to unsubscribe keeps subscribers alive. is correct. Unsubscribe in Dispose. It fits the requirement in the prompt about how is event memory leaks best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q93. Which option best describes INotifyPropertyChanged in C#/.NET?

A. An attribute. B. Replaces all events. C. Pattern for property change events in MVVM. D. A delegate.

Select an answer to check.

Answer: Pattern for property change events in MVVM.

The best option here is Pattern for property change events in MVVM.. Used by data binding. It fits the requirement in the prompt about which option best describes inotifypropertychanged in c#/.net. The remaining choices fail because they don’t satisfy the full definition.

Q94. What is the primary purpose of INotifyPropertyChanged?

A. Pattern for property change events in MVVM. B. An attribute. C. Replaces all events. D. A delegate.

Select an answer to check.

Answer: Pattern for property change events in MVVM.

For this question, Pattern for property change events in MVVM. is correct. Used by data binding. It fits the requirement in the prompt about what is the primary purpose of inotifypropertychanged. The remaining choices fail because they don’t satisfy the full definition.

Q95. Which statement about INotifyPropertyChanged is most accurate?

A. An attribute. B. Replaces all events. C. Pattern for property change events in MVVM. D. A delegate.

Select an answer to check.

Answer: Pattern for property change events in MVVM.

Pattern for property change events in MVVM. is the correct answer here. Used by data binding. It fits the requirement in the prompt about which statement about inotifypropertychanged is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q96. How is INotifyPropertyChanged best characterized?

A. Pattern for property change events in MVVM. B. Replaces all events. C. A delegate. D. An attribute.

Select an answer to check.

Answer: Pattern for property change events in MVVM.

Here, Pattern for property change events in MVVM. is the right choice. Used by data binding. This is the most accurate statement for how is inotifypropertychanged best characterized. The remaining choices fail because they don’t satisfy the full definition.

Q97. Which option best describes publish-subscribe in C#/.NET?

A. Decoupled communication via events/messages. B. Polling only. C. Direct method calls only. D. Pure RPC.

Select an answer to check.

Answer: Decoupled communication via events/messages.

In this case, Decoupled communication via events/messages. is correct. Foundational pattern. This is the most accurate statement for which option best describes publish-subscribe in c#/.net. The remaining choices fail because they don’t satisfy the full definition.

Q98. What is the primary purpose of publish-subscribe?

A. Direct method calls only. B. Decoupled communication via events/messages. C. Polling only. D. Pure RPC.

Select an answer to check.

Answer: Decoupled communication via events/messages.

The best option here is Decoupled communication via events/messages.. Foundational pattern. This is the most accurate statement for what is the primary purpose of publish-subscribe. The remaining choices fail because they don’t satisfy the full definition.

Q99. Which statement about publish-subscribe is most accurate?

A. Decoupled communication via events/messages. B. Pure RPC. C. Polling only. D. Direct method calls only.

Select an answer to check.

Answer: Decoupled communication via events/messages.

For this question, Decoupled communication via events/messages. is correct. Foundational pattern. This is the most accurate statement for which statement about publish-subscribe is most accurate. The remaining choices fail because they don’t satisfy the full definition.

Q100. How is publish-subscribe best characterized?

A. Pure RPC. B. Direct method calls only. C. Polling only. D. Decoupled communication via events/messages.

Select an answer to check.

Answer: Decoupled communication via events/messages.

Decoupled communication via events/messages. is the correct answer here. Foundational pattern. This is the most accurate statement for how is publish-subscribe best characterized. The remaining choices fail because they don’t satisfy the full definition.