Which sentence has an error in parallel structure? a) why don't you just sit down, shut up, and let someone else take over the meeting? b) the director was looking for a girl who could do action, comedy, and romance--preferably all at the same time. c) jane could never understand why her boyfriend left, why he didn't leave a note, and why she could never keep a boyfriend. d) whenever mary cooks cookies, she also eats half the dough, scalds the bottoms of the cookies, and she never cleans up her mess.