What do the lines say? There is no image so I can't help
The correct answer is sentence (5).
A sentence fragment means that it is only a part of a sentence; it is not complete. Given that it is incomplete, the fragment, aka subordinate/dependent sentence, has to be part of a larger, independent sentence, in order to make any sense. So if you combined sentence (5) with another one, it wouldn't be a fragment anymore.
The real meaning of euphemism friendly fire is term in military bases means accidentally attacking your own military unit hope this helps :)
