Professor Smith, along with his assistants ____ _on the project

Professor Smith, along with his assistants ____ _on the project day and night to meet the deadline.
A、work
B、working
C、is working
D、are working
【正确答案】：C
【题目解析】：【考点点击】本题考查主谓一致。【要点透析】主语是单数的时候,虽然后面跟 with, together with, more than, as well as,like, in addition to等引导的短语,谓语动词仍用单数形式。