ExplanationSome believe that due to humanity’s tendency to explore, the galaxy will eventually be colonized by trillions of humans. If that happens, the vast majority of humans who ever live would be alive during that colonization period.
We have no reason to think we are special in time, so if colonization will occur, we should probably be alive in that future era rather than now. But we are not alive during that future colonization period. Therefore, it’s unlikely such colonization will ever happen.
(A) is too simplistic and mischaracterizes it. Hence out.
(B) suggests a contradiction in premises, but there’s no explicit contradiction in what the argument accepts.
(C) is wrong because the argument does try to make a prediction about the future based on present facts/probability.
(D) captures it well: If colonization hypothesis were true, then event
E (we are alive in colonization era) is likely.
E has not occurred (we are not in colonization era). So hypothesis is probably false.
(E) describes making a far future prediction based on human tendencies, but that’s what the believers do, the scientist is rebutting that prediction, not making it.
Answer: D