I think PE is one ofsubjects of all.A. most importantB. important C. the most importantD.

问题补充：

I think PE is one ofsubjects of all.

A. most important

B. important

C. the most important

D. more important

答案：

A. most important

B. important

(答案→)C. the most important

D. more important

解析：本句符合one of the +形容词最高级+名词复数形式，因此只有答案C，符合这个结构。