your T-shirt is so cool.could you tell me ----

题目

your T-shirt is so cool.could you tell me ----
a where you buy it
b where do you buy it
c where you bought it
d where did you buy it
为什么答案是c
说明理由

答案

where引导从句,用陈述语气,所以b、d排除.因为已经穿着了,所以买的动作是过去发生的,用过去时,选c