B. The composer's faith in the instrument and his knowledge of it played an important role in his success as a solo performer.
Explanation:
Option B is the correct answer. It is correct pronoun-antecedent agreement.
We all know that a pronoun is a word used instead of a noun. An antecedent is known to be a word which a pronoun stands for in a sentence.
For example, in the sentence above, the antecedent is the "composer" and the pronoun that refers to the antecedent is "his". We can see that the pronoun agrees with the antecedent. In pronoun-antecedent, the pronoun in the sentence must agree with its antecedent in number. This means that a singular pronoun must replace a singular noun while plural pronoun must replace a plural noun.
