If both of the child references of a binary tree node are non-null, it follows that the node must be ____.
A)a child node
B)the root node
C)a leaf node
D)an interior node

Question

Quizplus · Accepted Answer

If both child references of a binary tree node are non-null, then the node must have both a left and a right child, and is therefore an interior node (not a leaf node). It cannot be the root node as the root node has no parent node.

If Both of the Child References of a Binary Tree