\(z = 4x + 6y \)
Let's substitute the coordinates of each corner point into the objective function:
For point \((0, 2): z = 4(0) + 6(2) = 12\)
For point \((3, 0): z = 4(3) + 6(0) = 12 \)
For point \((6, 0): z = 4(6) + 6(0) = 24 \)
For point \((6, 8): z = 4(6) + 6(8) = 72 \)
For point \((0, 5): z = 4(0) + 6(5) = 30 \)
From the evaluations, we can see that the minimum value of z occurs at two points, namely (0, 2) and (3, 0), both having a value of 12.
Therefore, the correct option is (D) only two points.