Correct answer: Qd31.Na7? (2.Qc8#[A]) but 1...O-O! 1.Qa4? (2.Qa8#[Б]) but 1...O-O! 1.Qa6? (2.Qa8#[Б]/Qc8#[A]) but 1...O-O! 1.Qb4?? (2.Qb8#/Q:e7#) 1...K