Which of the following statements are correct? 1 An argument passed to a ref parameter need not be initialized first. 2 Variables passed as out arguments need to be initialized prior to being passed. 3 Argument that uses params keyword must be th

Which of the following statements are correct?

1 An argument passed to a ref parameter need not be initialized first.

2 Variables passed as out arguments need to be initialized prior to being passed.

3 Argument that uses params keyword must be the last argument of variable argument list of a method.

4 Pass by reference eliminates the overhead of copying large data items.

5 To use a ref parameter only the calling method must explicitly use the ref keyword.