高考英语问题Try _______ she might, Sue couldn't get the door open.

高考英语问题
Try _______ she might, Sue couldn't get the door open.
A. if B. when C. since D. as
答案是D
句意：Sue尽力了,但还是打不开门.
问题：①这里是考察让步状语从句的倒装句,那题目中状语从句是指逗号前面的话还是后面的话?
②还有,Try as she might 倒装前的语序为 as she might try,might有可能,能 的意思,try是尝试的意思,那么句子的意思岂不是:"正当她能尝试时",这里为什么会有尽力的意思呢?
③还有B选项 when 为什么不能选呢?当as引导让步状语从句都要倒装吗?