Insert the Missing Code in the Following Code Fragment

Multiple Choice

Insert the missing code in the following code fragment.This fragment is intended to create an iterator and access the first element in a tree.

A) Iterator<String> iter = aTree.iterator() ;
B) Iterator<String> iter = aTree.iterator<String>() ;
C) Iterator<String> iter = String.iterator() ;
D) Iterator<TreeSet> iter = aTree.iterator() ;