单选题
Smoking

Since 1939, numerous studies have been conducted to determine whether smoking is a health hazard. The trend of the evidence has been consistent and indicates that there is a serious health risk. Research teams have conducted studies that show beyond all reasonable doubt that tobacco smoking is associated with a shortened life expectancy.
Cigarette smoking is believed by most research workers in this field to be an important factor in the development of cancer of the lungs and cancer of the throat and is believed to be related to cancer of some other organs of the body. Male cigarette smokers have a higher death rate from heart disease than non-smoking males. Female smokers are thought to be less affected because they do not breathe in the smoke so deeply.
Apart from statistics, it might be helpful to look at what smoking tobacco does to the human body. Smoke is a mixture of gases, vaporized chemicals, minute particles of ash and other solids. There is also nicotine, which is powerful poison, and black tar. As smoke is breathed in, all those components form deposits on the membranes of the lungs. One point of concentration is where the air tube and bronchus divides. Most lung cancer begins at this point.
Filters and low tar tobacco are claimed to make smoking to some extent safer, but they can only slightly reduce, not eliminate the hazards.

单选题 It is easy to determine whether smoking is hazardous.
A. Right B. Wrong C. Not mentioned
【正确答案】 B
【答案解析】[解析] 该题说的是：判断吸烟对健康是否有危害是容易的。但是，文章的第一句话是这么说的：自1939年以来，人们进行了许多次研究，其目的都是为了判断吸烟对健康是否是一种危害。可以看出判断吸烟对健康是否是一种危害并不容易。
单选题 Smoking reduces one's life expectancy.
A. Right B. Wrong C. Not mentioned
【正确答案】 A
【答案解析】[解析] 该题说的是：吸炯会缩短人们的预期寿命。该题来源于第一段最后一个句子中的子句：tobacco smoking is associated with a shortened life expectancy吸烟与人的预期寿命缩短有关。
单选题 Smoking, may induce lung cancer.
A. Right B. Wrong C. Not mentioned
【正确答案】 A
【答案解析】[解析] 该题说的是：吸炯有可能诱发肺癌。文章的第二段和第三段都讲到了吸烟与肺癌的关系。
单选题 There is evidence that smoking is responsible for breast cancer.
A. Right B. Wrong C. Not mentioned
【正确答案】 C
【答案解析】[解析] 该题说的是：有证据表明乳腺癌是吸炯诱发的。文章没有提及这回事。
单选题 Male smokers have a lower death rate from heart disease than female smokers.
A. Right B. Wrong C. Not mentioned
【正确答案】 B
【答案解析】[解析] 该题说的是：男性炯民死于心脏病的比率小于女性烟民死于心脏病的比率。文章没有直接比较男性烟民和女性烟民死于心脏病的比率，但有这么一句话：Female smokers are thought to be less affected because they do not breathe in the smoke so deeply. 女性吸烟者被认为受的影响较小，因为她们不深吸烟。从中可以推出的是：男性烟民死于心脏病的比率高于女性烟民死于心脏病的比率。因此该题的命题是错误的。
单选题 Nicotine is poisonous.
A. Right B. Wrong C. Not mentioned
【正确答案】 A
【答案解析】[解析] 该题说的是：尼古丁是有毒的。答案可在第三段找到。
单选题 Filters and low tar tobacco make smoking safe.
A. Right B. Wrong C. Not mentioned
【正确答案】 B
【答案解析】[解析] 该题说的是：有了过滤嘴和焦油含量低的烟草，吸烟是安全的。文章的最后一段(也是最后一句)是这么说的：据称，过滤嘴和焦油含量低的烟草在某种程度上使吸烟变得较为安全，但是它们只是略微减少而不是消除危害。因此该题的命题是错误的。