BMC, Inc. produces plastic bubbles used for packaging. During the current year, BMC incurred the following costs: Rent on manufacturing facility $ 250,000 Office manager's salary 150,000 Wages of factory machine operators 110,000 Depreciation on manufacturing equipment 50.000 Insurance and taxes on selling and administrative offices 30,000 Direct materials purchased and used 170,000 Wages paid to factory machine operators in producing the bubbles should be categorized as: O a period cost and recorded in the inventory account O a product cost and recorded on the income statement O a period cost and recorded on the income statement O a product cost and recorded in the inventory account