A、 It is a popular sport.
B、 It has a long history.
C、 It is rarely tried a second time.
D、 It is an adventurous activity.

【正确答案】 D

【答案解析】解析：短文开篇即提到现在有越来越多的人加入危险性运动的行列中寻求刺激，随后用了adventure和a risky activity反复强调其危险性，并以bungee jumping为例具体说明。故选D。

A、 Everyday life makes people bored.
B、 Too much work exhausts people.
C、 People are suffering too much stress.
D、 They're mentally and physically healthy.

【正确答案】 A

【答案解析】解析：短文提到，“……现代人因为生活安全、乏味而参加危险性运动”。A中的makes people bored对应文中的boring，故选A。

A、 It was quite stable and carefree.
B、 It was not easy to survive.
C、 People enjoyed a long healthy life.
D、 People needn't work hard for a living.

【正确答案】 B

【答案解析】解析：短文提到，以前人类生活时刻面临疾病、饥饿等生存威胁。B中的not easy to survive对应文中的lives were constantly under threat及acontinuous battle for survival，故B正确。

A、 They are effective as long as people take care.
B、 They are not a recommended way to relax.
C、 They are all right for some people.
D、 They are difficult to be accepted.

【正确答案】 C

【答案解析】解析：短文主旨在于介绍一些现代社会中受到关注的危险性体育运动，例如蹦极。尾句简要评论：对于一些人的问题，解决方案就是从类似蹦极这样的活动中寻求刺激。故选C。