Based on the excerpt, the statement that best strengthens Feldman´s claim that people are mostly honest is b. Feldman´s payment system was largely successful. His payment system is based on honesty, because he leaves the bagels and a cash basket in which anyone who took a bagel would leave cash, even if people could take a bagel and not pay, or even take money out of the basket, that did not happen. As he says "it was an honor-system commerce scheme, and it worked."
I would say it's the Historian because they study history or the past and have to interpret it so they can figure out how to teach it or stop it from happening again.
