http://classic.7sage.com/lsat_explanations/lsat-23-section-3-question-06/
I had some reservations in choosing answer choice C. I was able to eliminate all the others so answer choice C seemed most likely to be correct, but I wasn't 100% sure. The reason is that the premise states "The purse of a trader in the city "would probably" have contained a more diverse set of coins." and the C uses more definitive word, "had been brought". I think we don't know for a fact that it 'had been' brought by the pilgrims. It is a speculation. Since it is only a speculation that the purse would probably have contained a more diverse set of coins. I would think the correct answer would say "The purse... was probably brought . . . by a pilgrim."