— What do you think of Putin?

— He is an outstanding leader who _____ his reputation. [ ]

A. looks out for

B. comes up with

C. lives up to

D. looks forward to

放炮崩倒棚子的原因是因为支架架设质量差，放炮前没有检查或（）放炮地点附近的支架；爆破参数选择不合理，爆破后产生大块煤、岩抛向支架。