题目内容：

It took a long time for the connection between temperature and illness().A.to make B.to be made...
It took a long time for the connection between temperature and illness().A.to make B.to be made C.making D.being made

优质解答

it 是形式主语 connection是主语的一部分,the connection between temperature and illness to be made做主语,to be made做目的状语