There is such a problem we all should ．
A. as; pay attention to it
B. that; attract our attention
C. as; pay attention to
D. that; attract our attention to it
网友回答
A. as; pay attention to it
B. that; attract our attention
(答案→)C. as; pay attention to
D. that; attract our attention to it
解析：考查定语从句。先行词为a problem，pay attention to后缺少宾语，such… as 为固定结构，所以用as，并在从句中作宾语，故选C。