I'd love to hear people's thoughts on this, but in my opinion, a primary reason (D) is correct is that it maps to the author's reasoning the best (it conforms to the "gist" of the author's argument) and takes the author's premises closer to the conclusion. Leaving a gap here is tolerable because it's a PSA question.

This is one of two questions I missed in this LR set (the other one I ran out of time), and it's a bit alarming because I find that, in 70-up PTs, I've been missing as many as 2 questions in the Q7-Q12 range even in some sets where I'd get the rest of them correct. Is anyone else having this problem?

ffs stared at this question for half an hour and realized it's an agree question, not disagree; keep getting -2 on LR on questions 1-7 for some reason and not getting the harder ones wrong :/

I think a strategy that helped me to get to AC C) quickly is keeping track of the subjects described in the stimulus. The descriptions of the subjects in this stimulus are limited to subsets of "celestial objects" (stars and brown dwarfs) so any answer choices that describe a quality of “any celestial objects” are likely wrong for they'd be prescribing a quality to something not mentioned in the stimulus.

Yeah I think an answer with a "most" qualifier is usually pretty suspect in Necessary Assumption questions, because it's a very specific/ restrictive requirement (from more than half to the entire population). So I'd say in addition to switching "fatalities" to "head injuries," if we switch "most" to "at least some" that'd make the AC a more convincing candidate.

I think it's possible. I went from a ~162 to a ~172 (give or take 2 points on each end) on my PTs in about a month and half, but that happened after a few months of studying the core curriculum on here. Thinking hard about and having a really solid grasp on each question I missed (and those I didn't understand fully) was helpful. I found that I improved the most during a period when my mind became more focused and disciplined during studying.

And I second the comment about putting more effort on drilling LG, as it's the most learnable section of this test. (And I'm sure you heard this before but make sure you warm up before taking a PT or the actual test)

You got this!