单项选择题
（）is guaranteed by the full market supply and just-in-time logistics.
A.zero inventory B.stock C.inventory D.outsourcing inventory
单项选择题 （）has 3 specific points: fixed port, fixed line and announcing shipping time in advance.
单项选择题 （）is very convenient equipment for loading and unloading goods.
单项选择题 he area for unloading goods in warehouse is（）
