Visual Programming MCQs with Answers
Practice important Visual Programming MCQs with answers and explanations.
Multiple Choice Questions
Q641: What is the primary purpose of using async and await in C#?
- A: To simplify asynchronous programming and make the code easier to read and maintain
- B: To ensure that methods execute synchronously and block the main thread
- C: To eliminate the need for threads and concurrency in code
- D: To manage parallel execution of tasks without using the Task class
View Answer
A
Q642: How does the async keyword affect a method's return type?
- A: It allows the method to return a Task or Task
, enabling asynchronous operations - B: It automatically changes the method to return void for event handlers
- C: It ensures that the method's return type is always void regardless of its content
- D: It converts the method into a synchronous method that blocks until completion
View Answer
A
Q643: What does the await keyword do when used in an async method?
- A: It pauses the execution of the method until the awaited task completes
- B: It immediately executes the awaited task in a new thread
- C: It converts the method into a synchronous operation that blocks until the awaited task finishes
- D: It ensures the method runs in parallel with other tasks
View Answer
A
Q644: How does the Task.Run method handle asynchronous operations compared to a direct method call?
- A: It schedules the method to run asynchronously on a thread pool thread
- B: It executes the method synchronously in the calling thread
- C: It creates a new thread for each operation, which is inefficient
- D: It blocks the calling thread until the operation completes
View Answer
A
Q645: What is the difference between async Task and async Task<T> methods?
- A: async Task methods do not return a result, while async Task
methods return a result of type T - B: async Task
methods are synchronous, while async Task methods are asynchronous - C: async Task methods can only be used with void, while async Task
methods can use any return type - D: There is no difference; both return the same type of Task
View Answer
A
Q646: In the code provided, what is the purpose of the TaskCompletionSource<T> class?
- A: It allows manual control over task completion, including setting results and handling exceptions
- B: It automatically manages the lifecycle of tasks without requiring manual intervention
- C: It simplifies the creation of tasks by automatically providing results and handling errors
- D: It ensures that tasks are always executed in parallel without exceptions
View Answer
A
Q647: How does await Task.Delay(5000) behave in an asynchronous method?
- A: It pauses the method's execution for 5 seconds without blocking the main thread
- B: It blocks the entire application for 5 seconds
- C: It executes the delay synchronously, blocking the calling thread
- D: It creates a new thread that waits for 5 seconds before continuing execution
View Answer
A
Q648: What is the advantage of using CancellationToken in asynchronous methods?
- A: It allows methods to be cancelled mid-execution and supports cooperative cancellation
- B: It automatically cancels tasks after a specified time without needing additional code
- C: It ensures that tasks are executed sequentially without any interruptions
- D: It manages thread synchronization and avoids race conditions
View Answer
A
Q649: How is progress reporting handled in asynchronous methods according to the content?
- A: By using IProgress
interface or Progress class to report progress updates in a thread-safe manner - B: By directly updating the UI with progress information on the main thread
- C: By using global variables to track progress and update them from different threads
- D: By handling progress reporting through synchronous methods only
View Answer
A
Q650: What does Task.WhenAny do in task combinators?
- A: It returns the first task that completes among the given tasks
- B: It waits for all tasks to complete and returns the results of the fastest one
- C: It combines the results of multiple tasks into a single task
- D: It cancels all tasks except for the first one that completes
View Answer
A