aueddonline Think recursive solution. First thing, think about the recursive step. How do you know which subtree has the most levels ? You have to compare obviously:
if (LevelCount(root->left) > LevelCount(root->right))
do someting else
Next, think about the terminating condition. That will stop you from running forever.
You put those two together and you should be fine. Make sure you are counting correctly too. If you only have root node (no children) is that 0 levels or 1 level ??