I think it's B........................................................
Needs some context whos buck is this from a book ? Or a movie?
The answer is:
My mother is very tall but my father is even taller.
Conjunctions join clauses, words and phrases and they are usually used to avoid a sequence of short sentences. For example, <em>and, but, </em>and <em>or</em>.
In this case, the most suitable sentences to combine with a conjunction like "but" are the ones whose subjects are related (mother and father) and whose predicates have a similar structure: both describe height and one has a comparative form of the adjective tall, so they can be easily joined.
