(education) A question where several answers are presented and the respondent must choose the correct one.

(figuratively) A question that is very important and/or difficult to answer.

Alternative form of million-dollar question

Used to encourage people to seek knowledge by asking questions, no matter how silly the questions may appear to be.

(UK politics) A topical question asked of the government by a member of the House of Lords, requiring an immediate response.

(logic) an informal fallacy. It is committed when someone asks a question that touches upon more than one issue, yet allows only for one answer.

Alternative spelling of chicken-or-egg question

Alternative spelling of chicken-or-egg question

One should not make a judgement until one hears the other side.

(dated, US) Synonym of million-dollar question