------Is that the small company you often refer to?-----Right,just the one you know I used

------Is that the small company you often refer to?
-----Right,just the one you know I used to work for years.
A. that
B. which
C. as
D. where

A. thatB. whichC. as(答案→)D. where解析：本题考查定语从句。先行词the one在从句中做地点状语，用连接副词where 。you know为插入语，与先行词the one无直接关系。【标签】带插入语的定语从句

我明天再问问老师，叫他解释下这个问题