is well known to us all is Yao Ming has become the boss of the Shanghai Sharks who atten

问题补充：

is well known to us all is Yao Ming has become the boss of the Shanghai Sharks, who attended the opening ceremony of the new CBA season on Dec. 19, .

A. It; that

B. What; what

C. As; that

D. What; that

答案：

A. It; that

B. What; what

C. As; that

(答案→)D. What; that

解析：考查主语从句和表语从句：第二个is前面的都是主语从句，主语从句中缺少的是主语，用what引导主语从句，is后面的是表语从句，从句中意思完整，用that连接。句意：我们都知道的是姚明成为了上海Sharks的老板，在的12月份参加了CBA赛季的开幕式。选A。