The distinctive yellow-green colors of Vincent van Gogh's

C
B&D - the two other choices are looked at, seem to be identical to me

The point of the passage is - The yellow-green color in VG's painting may be due to Drug Digitalis.
How is the author making this point? by providing evidences
A- not A because there is no clear indication of the cause(because VG used Drug Ditialis in his paintings) and the effect (the yellow green color in VG's paintings)
B- circumstantial evidence is indirect evidence. It is the cirumstances that surrond the facts that can be used to prove a point. In our case- Dr's potrait happen to have the plant from which the drug is made. Therefore VG used it in his painting. a good try but is still too far fetched.
so B maybe.
C - yes, its clear that there is connection between Drug and VG's paintings but I am not convinced if that is strong evidence to prove the point.
D- I strongly feel that the author is proving the point by citing some form of documented evidence ( Dr's potrait with the plant from which the drug is made-Dr is VG's physician). Whether we are convinced is another issue but the author is making a point by citing specific documented facts.
E- is out of scope.
so between B and D, I tend to choose D

I'll go with C
I agree with ur point on D ... but shouldn't we consider this to be out of scope?

The author ventures that a certain drug may have inspired VG’s paintings. It is clear that s/he does not have any solid evidence that would stand in court; note the choice of words. Yes, digitalis was a commonly prescribed drug but whether VG used it at all or was addicted to it we cannot ascertain. Yes, some doctor treated VG, but whether VG was treated from one disease or other we have no way of knowing. Yes, the good doctor is holding a bunch of flowers from which the drug is made, but to say that this is documentary evidence of some sort or that there is a double-entendre would be making unwarranted inferences. I believe this is exactly what they call circumstantial evidence (B). Just my two cents.

My choice (B),
(D) is close but I don't believe that it is correct because passage doesn't connect digitalis to van Gogh's paintings, passage merely states that it is evident that the cause of Van Gogh's specific color effects were generated by digitalis held by physician(I presume) and this was just circumstantial(the tone of passage sounds like it).

What's the OA.

well, B is OA on this one. This is Peterson's LSAT question. There are no official explanations given but I am not too fond of this question either. I'll try to find some better ones next time

PS nice reasoning ob

This sentence uses modifiers wrongly, got B, anyway.
author tried a nexus between the drug and the effect. From the last sentence it can be inferred that foxglove would have caused the effect and the painting testifies the presence of foxglove during Gogh's time. [/quote]