A、 Smoke.
B、 Tar.
C、 Nicotine.
D、 Ashes.

【正确答案】 C

【答案解析】解析：短文开头便介绍了香烟使人上瘾的主要原因在于其成分尼古丁。故选C。

A、 Because they feel nervous when not smoking.
B、 Because they have nothing to do when not smoking.
C、 Because they feel no taste in their mouths without cigarettes.
D、 Because they don't know how to establish new contacts without cigarettes.

【正确答案】 A

【答案解析】解析：吸烟者在戒烟时因为已经对尼古丁上瘾，不吸则紧张、感觉不适，从而导致戒烟困难。故选A。

A、 The better taste that is less addictive.
B、 The reduced risk to their health.
C、 The higher status they symbolize.
D、 The less smoke they give out.

【正确答案】 B

【答案解析】解析：录音最后指出因戒烟困难，同时又想降低吸烟对健康的危害，焦油含量低的香烟因此广受欢迎，故选B。