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Question 1:  What is the main use of WeakRef in JavaScript?

(A) To prevent garbage collection of objects

(B) To hold a reference without preventing garbage collection

(C) To store objects permanently in memory

Question 2:  Which method is used to get the referenced object from a WeakRef?

(A) .ref()

(B) .get()

(C) .deref()

Question 3:  What happens if you call .deref() on a WeakRef whose object has been garbage collected?

(A) Returns null

(B) Throws an error

(C) Returns undefined

Question 4:  Why is WeakRef generally avoided for normal data storage?

(A) It is too slow

(B) Garbage collection can remove the object anytime

(C) It cannot be used inside classes

Question 5:  What does FinalizationRegistry help with?

(A) Detecting memory leaks automatically

(B) Running cleanup code after an object is garbage collected

(C) Storing final versions of objects

Question 6:  Which method is used to register an object in FinalizationRegistry?

(A) .watch()

(B) .register()

(C) .track()

Question 7:  In FinalizationRegistry.register(object, heldValue), what is the purpose of heldValue?

(A) The value passed to the cleanup callback after GC

(B) The memory address of the object

(C) The name of the object’s class

Question 8:  Which of the following is TRUE about WeakRef?

(A) It prevents garbage collection of objects

(B) It allows objects to be garbage collected even if referenced

(C) It throws an error if the object is collected

Question 9:  Which of these is a valid way to create a WeakRef?

(A) new WeakRef()

(B) new WeakRef(object)

(C) WeakRef(object)

Question 10:  Which scenario is a good use case for FinalizationRegistry?

(A) Storing all application settings

(B) Automatically releasing file handles when objects are deleted

(C) Keeping objects alive forever