Correct answer: Be21...e3 2.Ba4# 1...c4 2.Nd4# 1.R:f5?? zz 1...c4 2.Nd4# but 1...e3! 1.Kg2?? zz 1...c4 2.Nd4# 1...e3 2.Ba4# but 1...g3! 1.Kh2?? zz 1...c4
