Am I dumb for not assuming that this "prolonged darkness followed by exposure to sunlight" was on a 24 hour day/night cycle?

I think it depends. First time I took it, I got it because I wasn't sure how I was going to do. Next time I don't think I will use it.

dafuq obtains

Yes, I believe that E is correct because the hypothesis in the stimulus is stating that the company must be adding buses to gain new customers. The only answer choice that would challenge this conclusion is E, because E explains that an alternate hypothesis would be that they are not trying to gain new customers, but are introducing these services to current customers.

Shouldn't never be listed as a logical indicator in group 4 (negate, necessary?)

#4 I'm a little confused. Wouldn't the necessary condition be "internally consistent" in order to make the "scientific theory plausible" (sufficient)? It seems like we have been following sufficient > necessary so this one is throwing me off because I had internally consistent > plausible..