It took a long time for the connection between body temperature and illness.A. to makeB.

问题补充：

It took a long time for the connection between body temperature and illness.

A. to make

B. to be made

C. making

D. being made

答案：

A. to make

(答案→)B. to be made

C. making

D. being made

解析：考察分词用法。The connection与make构成被动关系，所以使用被动形式。固定句型为：it takes sb some time to do sth;这个句型里使用不定式，这里也就是使用不定式的被动语态。