Which of the following methods is used to copy elements from one ArrayList to another?Question 2Answera.Collections.copy()b.duplicate()c.clone()d.copy()

To determine the correct method for copying elements from one ArrayList to another, let's analyze the options presented:

1. a. Collections.copy(): This method is used to copy elements from one list to another. However, it requires that the destination list must be the same size as the source list or larger. This is the correct choice.

2. b. duplicate(): There is no method named duplicate() in the ArrayList class or in the Collections framework in Java.

3. c. clone(): This method can create a copy of the ArrayList, but it does not directly copy the contents to another pre-existing ArrayList. Instead, it creates a new ArrayList instance that is a shallow copy of the original.

4. d. copy(): This option does not pertain to any known method in the context of ArrayList or the Collections framework.

Final Answer

The correct answer is a. Collections.copy(), as it effectively copies elements from one ArrayList to another, subject to the condition regarding size.