Perhaps Taobao is Asia’s largest and most popular retail（零售的）network platform , people can buy and sell a great variety of things .
A. which
B. where
C. when
D. that
网友回答
A. which
(答案→)B. where
C. when
D. that
解析：：考查定语从句。本题考查定语从句关系词。先行词是network platform，定语从句中的主语是people,谓语动词是buy and sell,宾语是a great variety of things.句子很完整，所以使用关系副词，先行词是指地点的，故使用where. B 正确。