the answer is ‘implied’, assuming that this is the definition to the word connotation.
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.
stories of adventures
He was especially fond of ‘Lives of the Noble Greeks and Romans
The sentence that uses parallel structures is B) My three favorite activities are writing, reading, and going to the library.
A parallel structure means that the same form of a verb is used in a sentence, and as you can see, here only gerunds are used - writing, reading, going - they all have -ing in the end.
The other sentences don't have a parallel structure because they don't use the same forms.