There are, of course, bad teachers as well as ______.

A.good one

B.some good

C.good ones

D.those good

答案及解析： C

解析：

句意：当然有一些坏老师也有一些好老师。one 是泛指，同名异物，根据前面bad teachers，后面应用good teachers，为了避免重复，用ones 来代替teachers，所以选C。