Correct answer: Nb6+1...Ke4[a] 2.Q:e3#[A] 1...Kc5/[б]/ 2.Q:b4#[Б] 1...B:d5 2.Q:d5#[C] 1.Nf4+? 1...Ke4[a]/Qd6 2.Q:b4#[Б] 1...Bd5/Bd7 2.Q:d5#[