Hey Pradeep! Thanks for the question.
Here we're asked to justify the reasoning, which really means we're looking for an assumption that strengthens the argument. The argument breaks down like this:
Climbers shouldn't attempt to climb Mount Everest for two reasons: the risk of death or serious injury is very high, and climbers' reports dispel the notion of gaining "spiritual discovery."
So, what's the logical gap that needs filling in? Well, is it a given that we shouldn't do something if it's risky and doesn't lead to spiritual discovery? Maybe those are the very reasons we should do it -- who knows?
(B), the correct answer, makes our assumption explicit. The argument tells us that climbing Mount Everest is dangerous and unlikely to lead to spiritual discovery. So it definitely falls under the category of "dangerous activities that are unlikely to result in significant spiritual benefits" (though you could quibble about the distinction between discovery and benefits). If you accept the principle that such activities should be avoided, then you'd have to agree that climbers shouldn't try to scale Everest.
(A) has two major flaws. First, you should always be on your guard when you see the word "primarily." The argument doesn't say anything about spiritual discovery being the primary goal. Second, though this answer does fill the gap between risk and not attempting the climb, it doesn't fill in the other gap, because it doesn't address the point about spiritual discovery being unlikely.
(C) is out of scope. Who's talking about legal prohibition?
(D) is out of scope. We're not interested in whether spiritual experiences are possible, we're interested in whether climbing Everest is a good idea.
(E) might be tempting, but it doesn't really affect the conclusion one way or another. Should people attempt to climb Mount Everest or not?
Pradeep, does that clear things up for you? Let me know if you have any more questions.
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