阅读下面短文， 把A---D四个句子填入文中空缺处， 使短文内容完整、正确，然后完成第70小题。( 每小题2分 ，共10分 )
More and more people around the world are joining in dangerous sports. Some people climbed the highest mountains, some traveled into unknown parts of the world, some sailed small boats across the largest sea. 小题1:
Bungee jumping ( 蹦极 ) and motorcycle racing are quite dangerous sports. Bungee jumping only lasts a few minutes or even seconds. You jump from a high place , 200 meters above the ground , and there is a rubber band ( 带子 ) tied to your legs. 小题2:
About 2,000,000 people around the world have tried bungee jumping.
Why do people join in these dangerous sports? Some scientists say that it is because modern life has become safe and it is not interesting. 小题3: They had to go out and look for food, and life was like a fight but was interesting.
小题4: They live and work in safe places, buy food in shops, and there are doctors and hospitals to look after them if they become ill.
小题5:Which of the following is WRONG?
A．People like to join in dangerous sports because they need excitement.
B．Traveling into unknown parts of the world is not a dangerous sport.
C．In bungee jumping, you jump down with a rubber band tied to your legs.
D．In the past, people lived in danger because the living condition was poor.
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