问题
Could you tell me_______- Every four years.
A:how often theOlympic Games take place
B:when theOlympic Games are held
C:how often arethe Olympic Games held
D:how often theOlympic Games were held
B:when theOlympic Games are held
C:how often arethe Olympic Games held
D:how often theOlympic Games were held
正确答案是：
