An Iterator Is Currently Pointing to the Correct Location for Insertion

Multiple Choice

An iterator is currently pointing to the correct location for insertion or removal of a doubly-linked list.Which of the following statements about doubly-linked list operations is correct?

A) The most expensive operation of a doubly-linked is to add an element at the end.
B) The most expensive operation of a doubly-linked is to remove an element at the end.
C) The most expensive operation of a doubly-linked is to add an element in the middle.
D) The most expensive operation of a doubly-linked is to add an element at the front.