C. Loud noises disturbed the neighbors.
Among the choices given above, only this sentence expresses
a complete thought. A sentence is defined as words meaningfully grouped to
express a complete thought. Most of the time, it has a subject and a predicate.
In this sentence, the complete subject is ‘loud noises’ and the complete predicate
is ‘disturbed the neighbors’. Basically, the sentence conveys the meaning that
the neighbors are disturbed by loud noises. All the other choices are phrases
or sentence fragments.