C - all the above. In social situations, I will often start out extroverted and after I crash and burn in a few conversations, I shut down. When hypomanic, I don't shut down and don't leave crash sites until I have scorched the earth. I am conscious enough of it to avoid situations like the break room, where not respecting social taboos can be an HR issue. I just get my coffee and head back to my office muttering "STFU, STFU, STFU..." under my breath.