Mastering Java: The Ultimate Quiz for 'Thinking in Java'

What does the add method suggest in the context of Collection?

1. Removes an element

2. Inserts an element at a specific position

3. Ensures the collection contains a specific element

4. Deletes the specified element

The correct answer is: Ensures the collection contains a specific element

The add method in the context of a Collection is used to ensure that a specific element is present in the collection. This means that the method will only add the element if it is not already present in the collection. Option A is incorrect because it suggests that the method removes an element, which is not the case. Option B is incorrect because it specifies inserting an element at a specific position, which is not necessarily the case for the add method. Option D is incorrect because it states that the specified element is deleted, which contradicts the purpose of the add method.