I went home and _____ my schoolbag and started to help Mother do the cooking.        [ ]

A. put off  

B. dropped off  

C. turned off  

D. shut off

货物系固中，（）不是货物单元。

A.车辆、移动式罐柜

B.甲板上装载的木材

C.未永久固定在船上的装卸设备

D.集装箱、货盘