Consider the following integer linear programming problem: Max Z= 3x + 2x Subject to: 3x + 5x 30 5x + 2x 28 x 8 XX20 and integer The solution to the linear programming formulation is: x = 4.210, x = 3.473. What is the optimal solution to the integer linear programming problem (the optimal values of decision variables and the value of the objective function)? A. x = 2, X = 3, Z = 12 B. x=5, X-3, Z=21 C.x = 4, x = 3, Z = 18 D.x = 4, x = 4, Z = 20