Correct answer: Bd21.b8Q+?? 1...Ka4 2.Qbb4#/Qbb3#/Qa1#/Qcb4# 1...Ka6 2.Qb6#/Qa3#/Qa1# but 1...Rb7! 1.b8R+?? 1...Ka4 2.Qa1#/Q