Consider the Transportation Problem and Its Optimal Solution in the Tables

Multiple Choice

Consider the transportation problem and its optimal solution in the tables below. The cell Source 3 - Destination 3 is currently empty. What would be the change in the objective function if the largest possible amount were shipped using that route, leaving all the supply and demand conditions unchanged?
$\begin{array}{|l|r|r|r|r|r|}\hline \text { COSTS } & \text { Dest. 1 } & \text { Dest. 2 } & \text { Dest. 3 } & \text { Dest. 4 } & \text { Supply } \\\hline\text { Source 1 } & 12 & 18 & 9 & 11 & 105 \\\hline \text { Source 2 } & 19 & 7 & 30 & 15 & 145 \\\hline \text { Source 3 } & 8 & 10 & 14 & 16 & 50 \\\hline\text { Demand } & 80 & 60 & 70 & 90 & 300/300 \\\hline & & & & & \\\hline \text { Shipments } & \text { Dest. 1 } & \text { Dest. 2 } & \text { Dest. 3 } & \text { Dest. 4 } & \text { Row Total } \\\text { Source 1 } & 30 & 0 & 70 & 5 & 105 \\\text { Source 2 } & 0 & 60 & 0 & 85 & 145 \\\text { Source 3 } & 50 & 0 & 0 & 0 & 50 \\\text { Col. Total } & 80 & 60 & 70 & 90 & 300/300 \\\hline\end{array}$

A) 0
B) fifty units
C) a decrease of $9
D) an increase of $450
E) an increase of $630