I guess I would say E, but I would also make it quite clear to the person that I was talking to that *I* wasn't the one using the facilities, so to speak.

I am weird about bathroom stuff, though. If I am walking with another woman into the bathroom, I would strongly prefer that we pause the conversation while we each enter our cubicles. I would like to complete my business while pretending that there isn't another person just inches away from me thinking "Man, she must have had beans last night." or "Wow, drink much?".

It makes me crazy when someone continues the conversation (or worse, STRIKES ONE UP) while we're both peeing.