All the citizens here strongly insist those who ________ “harmful” advertisements in the streets ________ punished strictly.

A. putting up; will be   B. to put up; should be    C: being put up; shall be    D. put up; be

一定量的刚性双原子分子气体，开始时处于压强为P₀=10×10⁵Pa，体积为V₀=4×10^-3m³，温度为T₀=300K的状态，后经等压膨胀过程温度上升到T₁=450K，再经绝热过程温度降回到T₂=300K，则整个过程中气体对外做的功为（）。

A．500J

B．700J

C．400J

D．600J