The fragment that is made up of a complete subject is:
<em>D. the loudest musical instrumen</em>ts
Explanation:
A complete sentence can be split up into two main parts: the subject and the predicate. <em><u>The subject is what the sentence is talking about, and the predicate is what is being said about the subject.</u></em> Usually, the predicate contains the verb. In this case, options a, b and c describe a subject and they all contain a verb (blares, blasted, applauded). Option D does not contain a verb and something can be said about it. Therefore, option D is a fragment that is made up of a complete subject.