We’ve booked a room in the centre of town for the guests they can stay for three days.A.

问题补充：

We’ve booked a room in the centre of town for the guests they can stay for three days.

A. when

B. whom

C. which

D. where

答案：

A. when

B. whom

C. which

(答案→)D. where

解析：考察定语从句。本题定语从句的先行词是a room。后面定语从句中的句子结构很完整，故使用关系副词where指代先行词在句中作状语。就：我们已经在市中心为客人预定了一个房间，在那里他们可以住三天。When的先行词是表示时间的名词；whom和which都是关系代词，不能再句中作状语。故D正确。