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Ferguson Company manufactures 4,000 parts per year; the parts are used in the assembly of one of the company's products. The unit product cost of these parts is: Variable manufacturing cost $32 Fixed manufacturing cost 18 Unit product cost $50 The part can be purchased from an outside supplier at $40 per unit. If the part is purchased from the outside supplier, two-thirds of the fixed manufacturing costs can be eliminated. What would be the annual impact on the company's net operating income as a result of buying the part from the outside supplier? O A. $8,000 increase B. $8,000 decrease O C. $16,000 increase O D. $16,000 decrease