（）是当轿厢或对重超过下极限位置时，用来吸收轿厢或对重装置所产生动能的制停安全装置.
A.安全钳
B.限速器
C.端站减速装置
D.缓冲器
参考答案：D
Twenty years ago, his father was very rich and was________a farm. [ ]
A. in place of
B. in charge of
C. in sight of
D. in possession of
