that the ticket sales showed that the Shanghai Expo was one of the best ever held.A. It is

问题补充：

that the ticket sales showed that the Shanghai Expo was one of the best ever held.

A. It is reported

B. What is reported

C. What reported

D. As is reported

答案：

(答案→)A. It is reported

B. What is reported

C. What reported

D. As is reported

解析：这个句子中，it是形式主语，真正的主语是后面that引导的主语从句。what放在句首时，that前应加系动词be，此时that引导的是表语从句；非限制性定语从句中的谓语为被动式时，常用as做主语，但这时as引导的非限制性定语从句与主语从句间应用逗号隔开，而不是用that引导了。所以选A。