There are many websites， you can find almost all the necessary information.
A. where
B. from where
C. when
D. from when
网友回答
A. where
(答案→)B. from where
C. when
D. from when
解析：考查从句，从句you can find almost all the necessary information不缺少成份，先行词是websites，是个非限制性定语从句，from where相当于which，所以选B，句子意思“这有许多网址，从这里你可以找到自己所需要的信息”