The correct answer is: colony
An antecedent is a noun or pronoun to which another noun or pronoun refers. It usually goes before the pronoun ( ante means before ).
The pronoun has to agree in number ( singular or plural ) and person ( first, second or third person ) with its antecedent.
In the sentence, the antecedent of the interrogative pronoun what is the word colony. The word colony answers the question what ? and it is therefore its antecedent.
