Given the BinaryTree Class (Partially Shown Below), Select an Expression

Multiple Choice

Given the BinaryTree class (partially shown below) , select an expression to complete the static recursive helper method countLeaves, which returns the number of leaf nodes in the binary tree rooted at node n.

A) n.right == null
B) n.left == null || n.right == null
C) n.left == null
D) n.left == null && n.right == null