关于冲量和功，下列说法正确的是（   ）

A．冲量和功都是过程量

B．冲量和功单位相同

C．一个力所做功为零，其冲量必为零

D．一个力的冲量为零，其所做的功必为零

The countries that are being blamed for the extra greenhouse gases in the atmosphere are the rich and developed countries. On a different______, the developing countries feel they will suffer the most of it.

A．nod

B．note

C．norm

D．notion