Up to now, he has taken part in five English contests, in ( )

Up to now, he has taken part in five English contests, in ( ) he was the winner.
A、every one
B、each one
C、every of which
D、each of which
【正确答案】：D
【题目解析】：定语从句，先行词尾five English contests,关系代词在从句中为介词in的宾语，every为形容词，选项C错误，正确答案为D。