Answer (C) presented something that seemed like it would matter: maybe lots of people have already tried the eight foods. What does that mean for the recommendation? Maybe some people have already had reactions to some foods. But some people might have tried only six of the eight, so maybe they should still try the other two. Or maybe… you could speculate endlessly, but all paths lead to the same place: this choice doesn't impact whether the specific recommendation made is good or bad.