单选题 Could you have the assistant ______my office before he leaves today?

A、 (A) stop off
B、 (B) stop for
C、 (C) stop to
D、 (D) stop by

【正确答案】 D

【答案解析】Stop by is a two-word verb that means to visit someone briefly. Choice (A) means to interrupt a trip briefly. Choice (B) means to stop for a specific purpose (followed by a noun, as in stop for gas). Choice (C) means stop in order to complete an action.