5. (Maximum Grade: 5.0 points - Suggested Time: 5.0 minutes) Ball Company produces four products as summarized in the following exhibit. Labour is the production constraint at Ball Company. Ball Company has 400,000 minutes of labour time available in the upcoming period. What is the production plan that maximizes contribution margin in the upcoming period? a. A 60,000 units, B70,000 units, C50,000 units, D30,000 units. b. A60,000 units, B70,000 units, C0 units, D14,000 units. c. A- 0 units, B16,666 units, C50,000 units, D30,000 units. d. A -0 units, B70,000 units, C50,000 units, D30,000 units