用英语说数学老师可以省略所有格吗？

The conference was organized for all of the _ in the city.

A.mathematic teachers

B.mathematics‘s teachers

C.mathematics’ teachers

D.mathematics teachers

The conference was organized for all of the ________ in the city.
A.mathematic teachers
B.mathematics‘s teachers
C.mathematics’ teachers
D.mathematics teachers （答案。学科作定语，运用逻辑考虑问题，其他答案都讲不通。）

所有格是干什么的？老师是数学的？

除此之外，A mathematic man is clever, but is not a mathematics teacher.