Correct answer: Qa31. Qb7? 1... e:d5 2. Q:d5+ 2... Kf4 3. Qg5# 1... Kf5 2. Qf7+ 2... Ke5 3. Qf4# 2... Kg4 3. Qf3# But 1... Kd4! 1. Nc