问题补充：
is known to all is Diaoyu Island is part of China.
A. What; that.
B. It; that.
C. As; that.
D. What; what.
答案：
(答案→)A. What; that.
B. It; that.
C. As; that.
D. What; what.
解析：考查名词性从句。句意：我们都知道钓鱼岛是中国的领土。第一空填what，引导主语从句，主语从句中缺少主语，故用what;第二空填that，因为表语从句中不缺少任何成分，故用that引导。选A。
