The passage says "Marsalis ruled the jazz universe, enjoying virtually unqualified admiration as a musician and unsurpassed influence as the music's leading promoter" -- isn't this support for AC B?

Is there also a temporal flaw in the argument or not?

If the question stem had asked us to weaken the argument, would C be a correct answer?

I got A and the way I reasoned through it was that, taking this premise to be true, we eliminate the alternate cause that the Han purple was brought from somewhere else. Is this a fair analysis?

I struggled with D because I thought the phrasing "are likely to be ambiguous" was too weak to get us to the conclusion of "the survey's responses are also ambiguous." Is the reason this doesn't matter because the question is asking for most strongly support? Would this answer choice fail if the stem asked us what logically follows from the stimulus?