An interrogative pronoun implies to a pronoun that introduces a question. These words are also called pronominal interrogative. Associated terms include interrogative, “wh”-word, and question word, although these terms are generally not defined in exactly the same way.
In English, who, whom, whose, which, and what commonly function as interrogative pronouns. When followed by a noun, whose, which, and what function as determiners or interrogative adjectives. When they start a question, interrogative pronouns have no antecedent because they refer to precisely what the question is trying to find out.