完形填空

阅读下面短文，掌握其大意，然后从以下各题所给的四个选项(A、B、C和D)中，选出最佳选项。

　　Mt. Qomolangma was first conquered(征服) in 1918, when Sir Edmund Hillary and Sherpa Tenzing, his guide, became the first climbers to reach the top. People have tried more than 715 times to conquer the mountain, but not (1) successfully, yet every climber knows the (2). This doesn't stop teams of climbers from arriving at the base camp every year with the hope of reaching the top.

　　Two such climbers, two (3) ones, are Scott Fischer and Rob Hall. Fischer, an American guide with much experience, was (4) in a terrible storm which swept across the (5). A rescue team found him and his friend, but didn't (6) to bring Fischer to safety in the terrible conditions because he was dying. New Zealander Rob Hall, (7) experienced climber and guide, was lost near the top. These two men had something in common; they were both guides who (8) “tours” for less experienced climbers up the mountain.

　　There is a lot that can go (9) in an action to reach the top of Mt. Qomolangma: a (10) change in weather conditions or a wrong turning. Planes will only be sent to rescue if they have been paid (11) in advance. In spite of all this, there is a business in leading guided tours to the top. (12) mountain climbers can now pay $64,000 or more to achieve their aim.

　　Many people (13) how guides can (14) their inexperienced climbers when they fail to keep themselves alive. Steve Bell, also a guide who has (15) led a team to Mt. Qomolangma, believes that they are safer than others, because the guide can ask a (16) climber to turn back at any (17) if he feels that (18) is a danger to the team.

　　Whether these expeditions are safe or not, many climbers feel that they have turned Mt. Qomolangma into a business, like a park for the very rich. One (19), however, will always remain: it doesn't matter how much money you have, if you make a mistake on Mt. Qomolangma, the possible result will be (20).

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