Find the Maximum Value of the Objective Function and Where

Multiple Choice

Find the maximum value of the objective function and where it occurs,subject to the indicated constraints. ​
Objective function:
​
Z = 4x + 5y
​
Constraints:
​
X ≥ 0
​3x - y ≤ 9
2x + 3y ≥ 6
X + 4y ≤ 16
​​ ​

A) Maximum at (3,0) : 12
B) Maximum at (3,4) : 32
C) Maximum at (4,3) : 31
D) Maximum at (0,4) : 20
E) Maximum at (0,2) : 10