Correct answer: Rac11...K:d3 2.O-O-O# 1.e5?? zz 1...K:d3 2.O-O-O# but 1...Kd5! 1.Ra5?? (2.Rd5#) but 1...K:d3! 1.Ra6?? (2.Rd6#) but 1...K:d3! 1.Ra7??