MCQs on Multithreading and Asynchronous Programming | Visual Basic .NET (VB.NET)

Test your knowledge on multithreading, Task Parallel Library (TPL), and Async-Await keywords in VB.NET with these 30 multiple-choice questions. Perfect for students and developers aiming to master advanced programming concepts.

Introduction to Threads

1. What is the primary function of a thread in VB.NET?
   a) To execute a sequence of instructions concurrently
   b) To store data
   c) To handle exceptions
   d) To manage user input
2. Which of the following is used to create a new thread in VB.NET?
   a) Thread.Start()
   b) Thread.Create()
   c) Thread.Execute()
   d) Thread.Invoke()
3. What does the Thread.Sleep() method do?
   a) Pauses the execution of the current thread for a specified time
   b) Stops the current thread
   c) Resumes the paused thread
   d) Ends all threads
4. What does the Thread.Abort() method do in VB.NET?
   a) Terminates the current thread
   b) Pauses the current thread
   c) Resumes a thread
   d) None of the above
5. Which keyword is used to define a thread-safe method in VB.NET?
   a) Async
   b) Sync
   c) Lock
   d) Volatile
6. Which of these is the correct order to start a thread in VB.NET?
   a) Create -> Start -> Run
   b) Start -> Create -> Run
   c) Create -> Run -> Start
   d) Run -> Create -> Start
7. What type of method does a thread execute?
   a) Void method
   b) Function returning a value
   c) Procedure returning a string
   d) Procedure with no return value
8. What does the Thread.Join() method do?
   a) Waits for the thread to finish
   b) Starts a new thread
   c) Pauses the current thread
   d) Cancels the thread
9. How can you set the priority of a thread?
   a) Using Thread.Priority property
   b) Using Thread.PriorityLevel method
   c) Using Task.Priority method
   d) Threads don’t have priority levels
10. What method is used to check the state of a thread?
    a) Thread.IsAlive
    b) Thread.GetState()
    c) Thread.Status
    d) Thread.CheckStatus()

Task Parallel Library (TPL)

11. What is the purpose of the Task Parallel Library (TPL) in VB.NET?
    a) To manage exceptions in asynchronous programming
    b) To simplify parallel programming
    c) To optimize memory usage
    d) To create new threads manually
12. Which class is used to create a task in TPL?
    a) Task
    b) Thread
    c) BackgroundWorker
    d) ParallelTask
13. How do you execute a task asynchronously in TPL?
    a) Task.Start()
    b) Task.Run()
    c) Task.Execute()
    d) Task.Begin()
14. Which method in TPL is used to run multiple tasks in parallel?
    a) Parallel.For()
    b) Task.Run()
    c) Task.Start()
    d) Task.Invoke()
15. What does the Task.WhenAny() method do in TPL?
    a) Waits for the first task to complete
    b) Waits for all tasks to complete
    c) Runs tasks sequentially
    d) Cancels all tasks
16. Which method is used to handle exceptions in TPL?
    a) Task.Exception
    b) Task.ContinueWith()
    c) Task.HandleError()
    d) Task.Error()
17. What is a benefit of using TPL over traditional threading?
    a) Simpler code and better scalability
    b) More control over thread management
    c) Direct control of CPU core allocation
    d) None of the above
18. Which of these TPL methods runs a task that returns a result?
    a) Task.Run()
    b) Task.ContinueWith()
    c) Task.Factory.StartNew()
    d) Task.Result()
19. How do you cancel a task in TPL?
    a) Using Task.Cancel()
    b) Using CancellationToken
    c) Using Task.Stop()
    d) Using Thread.Abort()
20. What does Task.Wait() do in TPL?
    a) Blocks the current thread until the task completes
    b) Waits for the task to start
    c) Cancels the task
    d) Pauses the task

Async and Await Keywords

21. What does the Async keyword indicate in VB.NET?
    a) A method will run asynchronously
    b) A method will return a value
    c) A method will handle errors
    d) A method will run synchronously
22. Which of these is a requirement for using the Await keyword?
    a) The method must be defined as Async
    b) The method must be void
    c) The method must use threads
    d) The method must be a function
23. What happens if you use Await without Async in VB.NET?
    a) Compilation error
    b) The program will run slower
    c) The method will execute synchronously
    d) Nothing happens
24. Can the Await keyword be used in a method that does not return a Task?
    a) Yes, with exceptions
    b) No, it must return Task or Task(Of T)
    c) Yes, but it will not be asynchronous
    d) Only with specific frameworks
25. What does Async allow in VB.NET?
    a) Concurrent execution of methods
    b) Synchronous method calls
    c) Direct interaction with UI components
    d) Memory optimization
26. What happens when an exception occurs in an Async method with Await?
    a) The exception is automatically handled
    b) The exception is thrown after the Await completes
    c) The exception is not caught
    d) The method retries automatically
27. What is the return type of an Async method that uses Await?
    a) Task(Of T)
    b) Task
    c) Void
    d) String
28. Which method can be used to execute multiple asynchronous operations concurrently?
    a) Task.WhenAll()
    b) Task.Run()
    c) Task.WaitAll()
    d) Task.ContinueWith()
29. How do you handle a timeout in an Async method?
    a) Using Task.Wait()
    b) Using CancellationToken
    c) Using AsyncTimeOut
    d) Using Task.ThrowIfCanceled()
30. What happens when an Async method with Await completes?
    a) The method resumes execution from the point after Await
    b) The method terminates without resuming
    c) The method re-executes the task
    d) The method freezes

Answers