________ we can't join in the party．
A.It is a pityB.That is a pityC.It is a pity thatD.It is pity在线课程C
解析：
主语从句位于句尾，使用先行词it作形式主语。It+be+名词词组(no wonder, an honour, a pity, no surprise, a good thing)+that从句，其中that不能省略。故排除A、B、D三项。