The girl hid herself under the table ______ she could see everything taking place in the room.

A．after which

B．from where

C．from which

D．in where

从外设发出中断请求到CPU响应该中断，有两个控制条件起着决定的作用，它们是 (1) 和 (2) 。这两个条件分别由 (3) 和 (4) 控制。