Answer:
B). Book.
Explanation:
Adjective clauses are illustrated as the clause comprising of a subject and a verb beginning with a relative pronoun and functions as an adjective in the sentence. Such clauses express a deficient thought and therefore, require a complete thought and therefore, require to be attached to the main clause to offer a complete thought.
In the given sentence, the adjective clause 'that(relative pronoun) she(subject) borrowed(verb) yesterday' functioning as an adjective in the sentence that is modifying the noun 'book'. It answers the question 'which book' by (the one) 'that she borrowed yesterday'. Thus, option B 'book' is the correct answer.
