— Excuse me, what can I do for you?

— Yes. I'd like to place ________ advertisement for ________ used car in your paper. [      ]

A. the; a  

B. an; /

C. an; a  

D. /; the

按要求写出下列反应的文字表达式，并说明反应的基本类型

（1）点燃镁条做信号弹______；

（2）燃烧红磷______．