Answer:
1. Nobody will have ever climbed Jhomolhari.
Explanation:
Answer: it provides the example of sweating sickness
Explanation:
The second choice is a fragment, not a complete sentence.
I believe the correct choice is number one, because if you turn the sentence around, it answers the question of why the crowd is gathered. You may want to confirm on the website chompchomp.com (Grammar Bites).
Something that is argueable is debateable.