I would advise against this. No one likes to think about green things between teeth or farts and most men certainly don't want to think of women with the former or doing the latter. Also they might think you're being bitchy. Personally I'd think "well this girl has a pretty unrefined sense of humor...". Humor yes, but only if you're actually funny. I don't like to see anyone who sucks at humor attempt it. Girl or guy.
The blokes find you attractive but somewhat aloof. They are afraid to make their manly desires known to you in case you turn on them and ridicule them in public.
I've been known to do C often. It's like the thing just overloads and shuts down for a minute to reboot. But A is entirely possible. Happens to everyone at some point. You're probably more attractive than the average bassist, so that makes A and C pretty likely (at least for me, beauty can cause a mental overload while trying to make smart sounding conversation). Next time it happens, you should ask him out just to really throw a curve ball his direction haha. My brain would probably melt.
For some guys, it's a power move - make you feel uncomfortable or force you to respond a certain way by putting you in an awkward situation. Gives them a sense of dominance by putting you on the defensive. It can be a controlling behavior or way of dealing with his discomfort because he's interested in you by transferring that discomfort to you.
Well it might have been something else. Years of noisy work environments and even noisier band have really affected my hearing and sometimes people speak but I just don't catch it so maybe I've just smiled vacantly when people were expecting a reply too!
I would try not to over think it if I were you. People do and say all sorts of weird, awkward things for reasons that only they understand (I know I do), and you'll drive yourself mad trying to figure out their motives. Whenever I find myself questioning what someone's odd behaviour or words mean, I try to give them the benefit of the doubt that no harm or malice was intended, unless it was explicitly stated. Otherwise, I know I'll drive myself mad trying to figure out what the person was thinking, and just end up projecting my own insecurities or doubts onto their actions.
It was the moment of "I had all semester to turn our classroom friendliness into a real friendship or take my chance at something more, and now I've effing blown it because I won't see her again".