根据《工程咨询单位资格认定办法》的规定，凡新申请工程咨询资格的单位，一般应从（）资格做起。

A.甲级

B.乙级

C.丙级

D.暂定级

I feel that one of my main duties ______ a teacher is to help the students to become better learners. [ ] 

A. for

B. by

C. as

D. with