Working abroad for many years, he has made a big _______ and started a company of his own.

A．difference

B．fortune

C．progress

D．breakthrough

重庆天原化工厂发生氯气泄漏事故，救援人员使用了防毒面具，以下适用于填充防毒面具并吸附毒气的是（　　）

A．金刚石

B．炭黑

C．活性炭

D．石墨