— How long has your brother been working in this factory? — 　　　 he graduated from college

问题补充：

— How long has your brother been working in this factory?

— he graduated from college.

A. When

B. By the time

C. Until

D. Ever since

答案：

A. When

B. By the time

C. Until

(答案→)D. Ever since

解析：考查连词辨析。A当…时；B到…时为止（与完成时连用）；until直到…才…；ever since自从…；句意：—你的兄弟在这个工厂里工作了多久了？—自从她大学毕业到现在一直都在这个工厂里工作。故D正确。