After five hours'drive,they reached________they thought was the place they'd been dreaming of.[ ]

A. that  

B. where

C. which  

D. what

排管机在抓住钻杆时没有了动力源，可以依靠（）来提供动力打开绞车刹车使钻杆下放。

A、液压泵

B、手压泵

C、储能器

D、气泵