Well there are many catastrophic scenarios that we already overcome. You should consider educating yourself about the great filter. A great filter is a hypothetical barrier that each civilization can or cannot overcome. From here on things get a little complex so I won't bore you with them. But there are experts in this theory called great filter and I'm sure they can tell you a lot about.
Answer:
B) A kidney malfunction that removes more water than normal
Explanation:
Just took the test :)
Also, the answer choice is worded differently for me. The alternative answer is "A kidney malfunction that removes more water than normal".
I think that the correct answer is reactants of photosynthesis.
Answer:
Carbon dioxide turns into glucose and water turns into oxygen
