Correct answer: Ba71...Nef3 2.Q:e4# 1...Nc4 2.b:c4# 1...Nc6 2.Bc4# 1...Ngf3 2.Q:f7# 1...Ne6 2.Qb7# 1.Bb6?? (2.Rd4#) 1...Ngf3 2.Q:f7# 1..