单选题 If being carried out successfully, the plan will completely change the traffic conditions in the city.
A．carried B．is carried C．having been carried D．to carry

【正确答案】 A

【答案解析】[解析] 结构应用
本句考察的是省略的用法：当状语从句的主语和主句的主语相同时，状语从句可以用分词短语作状语。本句完整的句子应为“if it is carried out successfully...”，变成省略句时，直接用“if+过去分词”，因此A为答案。