In the 5 \times 5 grid shown, 15 cells contain \mathrm{X} 's and 10 cells are empty. Any \mathrm{X} may be moved to any empty cell. What is the smallest number of X’s that must be moved so that each row and each column contains exactly three X’s?
\begin{array}{|c|c|c|c|c|}
\hline \mathrm{X} & \mathrm{X} & \mathrm{X} & \mathrm{X} & \\
\hline \mathrm{X} & \mathrm{X} & \mathrm{X} & & \mathrm{X} \\
\hline \mathrm{X} & \mathrm{X} & & & \\
\hline \mathrm{X} & \mathrm{X} & & \mathrm{X} & \\
\hline & & \mathrm{X} & \mathrm{X} & \\
\hline
\end{array}
Answer Choices
A. 1
B. 2
C. 3
D. 4
E. 5