单选题 —Was the driving pleasant when you vacationed in Mexico (墨西哥) last summer?
—No, it______ for four days when we arrived so that the roads were very muddy.

【正确答案】 B
【答案解析】从句用过去时态，主句应该与之一致，因有"for four days"，所以应该用完成时态表示过去持续的动作。