Table 281 Refer to Table 28

Table 28.1 $\begin{array}{|c|r|r|}\hline\begin{array}{c}\text { Reduction in Emissions } \\\text { (in tons) }\end{array} & \begin{array}{c}\text { MC to Reduce Emissions by } \\\text { SteelPlant }\end{array} & \begin{array}{c}\text { MC to Reduce Emissions by } \\\text { Paper Plant }\end{array} \\\hline 1 & \$ 400 & \$ 200 \\\hline 2 & 500 & 280 \\\hline 3 & 600 & 320 \\\hline\end{array}$
Refer to Table 28.1.Suppose the government allows these two firms to trade pollution permits.The total cost to reduce emissions by a total of two tons could be as low as

A) $0.
B) $480.
C) $900.
D) $600.