Mark the letter A, B, C, or D on your...

Câu hỏi: Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
Metal and glass containers can be recycled, and several states are currently contemplating mandatory recycling for either.

A. be recycled   

B. and

C. currently contemplating       

D. for either