Correct answer: Bb71...Rd5 2.Qb4#/Qa3# 1...Rd4 2.Qc5# 1...R:d3 2.Qc5#/Qa3# 1...Rd7 2.Qc5#/Qb4#/Qa3# 1...Rd8 2.Q:d8#/Qc5#/Qb4#/Q