Help choosing my recommender: weaker letter from faculty with PhD, or strong letter from non-PhD industry boss?
Person B seem the best person to assess your at least &quot;academic related&quot; work. That said, in my (non-US) experience reference letters very, very rarely if at all play a major role when making decisions whom to admit, as long as they are &quot;kind of OKish&quot; and the writer has at least some qualification to write them. So you shouldn't be worried of making an all too big mistake here; chances are that your success will not rely on your recommender choice. I'd probably avoid Person C but I don't think Person A will do you much harm. If I were Person A, I'd have a look at your overall results, and mention positively if they are better than what you did in my class (which apparently isn't exactly bad either).