What is the antecedent of the interrogative pronoun What?

The antecedent of the interrogative pronoun 'which' will be the choice of two or more antecedent nouns or pronouns that will answer the question.

Examples:

Which pair of shoes looks the best with this dress?

The antecedent will be the answer to the question, such as 'the black ones' or 'the suede pair', from the choices already known to the speaker and the listener.

You might consider the noun phrase 'pair of shoes' as the antecedent, but the sentence can as easily be, 'Which looks best with this dress?' The choices being 'shoes' is already known to the speaker and the listener.

Chocolate, vanilla, or strawberry, which is your favorite?

The antecedent is the noun for the one flavor of the three that the listener prefers.

hope this helped!

i think its a.

an ugly duckling is teased by the other ducklings. when she grows up, however, the ducklings discover that she is a beautiful swan