Refer to the Data Provided in Table 16 -Refer to Table 16

Refer to the data provided in Table 16.1 below to answer the following questions.
Table 16.1 $$\begin{array} { c l l } \text { Tons of Salt } & \text { MC } & \text { MSC } \\\hline 1 & 10 & 20 \\2 & 20 & 30 \\3 & 30 & 40 \\4 & 40 & 50 \\5 & 50 & 60\end{array}$$
-Refer to Table 16.1. The marginal damage costs imposed on society from processing four tons of salt are

A) $2.50 per ton of salt.
B) $10 per ton of salt.
C) $12.50 per ton of salt.
D) indeterminate from this output.