Everyone here will thank the firefighter for the things they have done to prevent fires the environment safer.
A. make
B. to making
C. to make
D. from making
网友回答
A. make
B. to making
(答案→)C. to make
D. from making
解析：这里prevent fires （“预防火灾”）的目的是to make the environment safer，动词不定式表目的；本题容易误选D. from making，这是因为受到prevent sth/sb from doing sth句型的误导。要特别注意。故选C。