Correct answer: Bb71...c:d5 2.B:b5# 1.R:b5?? (2.Rb6#/Rb7#/Rb8#/Rba5#) but 1...c:b5! 1.Ra3?? zz 1...K:b4 2.R3a4#/R5a4# but 1...c:d5! 1.Ra2?? zz 1
