You had better book rooms at the hotel in advanceyou should find no room on your arrival.

You had better book rooms at the hotel in advance you should find no room on your arrival.
A. so that
B. even if
C. in case
D. now that

A. so thatB. even ifC. in caseD. now that解析：选C。考查状语从句。句意: 你最好提前在旅馆订房间, 以防你到达时找不到房间了。in case意为“以防; 免得”, 引导目的状语从句。【变式训练】(2013·烟台模拟)We’d better stay here a little longer he turns up unexpectedly.A. although B. in case C. since D. if only选B。考查状语从句。句意: 我们最好在这里多待一会儿, 免得他突然出现。此处in case引导一个目的状语从句。【知识拓展】in case作为短语连词的用法in case作短语连词, 能引导状语从句。就其词义和语法职能来分, 可引导两种从句。其一: in case/just in case引导目的状语从句作“以免, 以备, 以防”等解。例如:He takes a torch in case it gets dark before he returns.他带了手电筒, 以备天黑以后回家之用。Please remind me of it again tomorrow in case I forget.请你明天再提醒我一下, 免得我忘记。其二: in case接条件状语从句, 意为“如果, 万一”。例如:In case we fail, we won’t lose heart.万一我们失败, 我们决不会失去信心。Take a hat with you in case the sun is very hot.倘若太阳很厉害, 你就把帽子戴上。In case he arrives before I get back, please ask him to wait.万一我回来前他先到了, 请让他等我。注意: in case引出的条件状语从句所表示的意义是“预防某种情况的出现”; 如果从句说的是一般的假设或条件, 则要用if。请比较:I’ll tell him about the matter if I meet him. 　(不用in case)Take an umbrella in case it rains. 　(不用if)在上下文意义很明确时, 有时可省去in case后从句的内容。例如:I don’t think it will rain, but I’ll take an umbrella in case(it rains).

就是这个解释