The window _____ ten minutes ago, and the room is bright now. [ ]

A. can be cleaned

B. is cleaned

C. was cleaned

D. will be cleaned

堆取料机取料时，需先检查尾车是否在取料位置，尾车与煤场主输送机是否连接好，各项检查完毕确认正常后，把斗臂对到待取料的煤料位置，待煤场主输送机按取料方向启动后，启动悬臂皮带，然后先启动补油泵，后启动回转泵，最后启动（），开始取料。