twice a year whether it is a car a bus or a truck is the rule that every driver must ob

问题补充：

twice a year, whether it is a car ,a bus or a truck, is the rule that every driver must obey in this city.

A. Examining

B. Examined

C. Being examined

D. Having been examined

答案：

A. Examining

B. Examined

(答案→)C. Being examined

D. Having been examined

解析：考查动名词用法。本句中being examined twice a year是动名词短语在句中做主语。动名词做主语表示经常性，习惯性的动作。句意：无论是轿车，公交车还是卡车，两年被检查一次是每个司机都必须遵守的规定。故C正确。