Binary search tree for a given set of words

Construct a binary search tree for the strings computer, back up disk D, local disk C, programs, windows, adobe, MS office, word, excel ,system32, back up file.

This question was given to us as homework. All I need to do is to draw a binary tree. Drawing a binary tree is not an issue for me, the problem here is that there are words (related to computers) instead of numbers, and to be honest, I don’t have enough info about computers.

After I searched on internet I found a possible answer (it’s in the following picture), but unfortunately my teacher says it’s not true. Ca you explain why?

Image is attached here