Solve the Problem $B$ Rates a 4 in Effectiveness, and an Hour of Regimen

Multiple Choice

Solve the problem.
-An athlete uses three different exercise regimens for increasing cardiovascular fitness. An hour of regimen A rates a 3 in effectiveness, an hour of regimen $B$ rates a 4 in effectiveness, and an hour of regimen $C$ rates a 5 in effectiveness. In any given week, the athlete can train at most 5 hours by regimen $A$ . In any given week the combined hours of regimens $A$ and $C$ may not exceed 9. In any given week the combined hours of regimens B and C may not exceed 10. How many hours of each regimen should the athlete perform in a week in order to maximize the increase in fitness?

A) 4 hours of regimen A, 5 hours of regimen B, 5 hours of regimen C
B) 5 hours of regimen $A, 6$ hours of regimen $B, 4$ hours of regimen $C$
C) 3 hours of regimen $A, 4$ hours of regimen $B, 13$ hours of regimen $C$
D) 0 hours of regimen A, 1 hours of regimen B, 9 hours of regimen C