The important sports festival,the Olympic Games,___held every four years.A was B were C is D are

问题描述:

The important sports festival,the Olympic Games,___held every four years.A was B were C is D are
并说明理由

选C吧,AB都是过去式,而这句说的是奥运会每四年举办一次,不存在过去情况.the olympic Games 用单数,不要被games迷惑,is held 被动语态是修饰the olympic Games这个短语而不是Games的.