There Are Four Resources and Four Jobs to Be Done

There are four resources and four jobs to be done. The time required for each resource to do each job is as follows: $$\begin{array} { c } \quad \quad \quad \quad { \text { Job (Hours) } } \\\begin{array} { l c c c c } \text { Resource } & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } \\\hline 1 & 5 & 8 & 7 & 7 \\2 & 4 & 9 & 5 & 9 \\3 & 6 & 9 & 8 & 7 \\4 & 7 & 6 & 6 & 9\end{array}\end{array}$$ What is the optimal assignment of resources to jobs?

A) 1 to A; 2 to C; 3 to B; 4 to D
B) 1 to B; 2 to D; 3 to C; 4 to A
C) 1 to C; 2 to B; 3 to A; 4 to D
D) 1 to D; 2 to B; 3 to C; 4 to A
E) 1 to A; 2 to C; 3 to D; 4 to B