Correct answer: Nd5+1...Ka7 2.Qc7# 1.R:b2?? zz 1...Ka7 2.Qc7# but 1...B:b2! 1.Rc3?? zz 1...Ka7 2.Qc7# but 1...d:c3! 1.Qb5+?? 1...Ka7 2.R