________ is often the case with her, my mother talked about my study for at least half an hour nonstop before she drove me to school yesterday.

A．As

B．Which

C．What

D．That

发烟硝酸，硫酸与有机物接触会有什么后果（）

A、会引起自燃

B、会引起爆炸

C、会引起锈蚀

D、无关