Plastics and other similar rubbish that does not ______ may not be thrown into  the sea anywhere.

A．break down

B．break away

C．break off

D．break through

切丝机切丝过程中停机打开机头检查刀门，发现下刀门刃口挂有烟丝，粘有较厚（），可能刀片与刀门间隙过大。