Person A says he recently read that Brand X is manufactured in China. He asks if this is true. Person B responds: "If this is a question about Brand X's integrity. Ask yourself why Brand X isn't up front about where it is actually being manufactured."

This reminds me of the GMO labeling paradox... if manufacturers are against GMO labeling, then the public wonders what they are hiding, and avoid GMOs. If they label them, then the public wonders why they need to be labeled, and avoid GMOs.

Person B should just answer the question (assuming person B has that information). However, person be is making an assumption to the motivation of the question (not necessarily fallacious) then asking a loaded question (the assumption built in is that Brand X isn't up front about their manufacturing--they might be, but it was simply missed by person A). It can also be a Red Herring if Person B's response was meant to throw Person A off from learning that the product might have been manufactured in the USA (assuming that is a good thing).