The correct answer is B but still, I couldn’t get it. Please rephrase it. It’s from The Big Book.
I think the probable confusion in this question would arise from “stopped short of” which means she “failed” to suggest that the conference was near collapse (that the conference is bad). Since this idea should contrast the first idea with the blank (because of While), it means the delegate (she) initially sought to decrease the optimism regarding the conference. Thus, B is the only answer that makes sense.