if subjects (X and Y) are placed in Either X or Y type of construction then the closest subject decides the singular or plural form of verb.

Every Monday,

either the math department chair or the members of the department posts a challenge problem to the student body, but usually it is so difficult that they cannot solve it in a week’s time.

(A) either the math department chair or

the members of the department posts a challenge problem to the student body, but usually it is so difficult that they

(B) either the math department chair or

the members of the department post a challenge problem to the student body, but usually the problem is so difficult that the students

(C) either the math department chair or

the members of the department posts a challenge problem to the student body, but usually the problem is so difficult that they

(D) either the members of the math department or

the department chair posts a challenge problem to the student body, but usually it is so difficult that

they(E) either the members of the math department or

the department chair post a challenge problem to the student body, but usually the problem is so difficult that the students

_________________

Piyush K

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