The total cost of the optimal solution to a transportation problem

A. is found by multiplying the amounts in each cell by the cost for that cell for each row and then subtracting the products of the amounts in each cell times the cost of each cell for the columns.

B. is calculated by multiplying the total supply (including any dummy values) by the average cost of the cells.

C. can be calculated based only on the entries in the filled cells of the solution.

D. cannot be calculated from the information given.

E. can be calculated from the original northwest corner solution.