NCL follows a policy of allocating all common costs equally among its profit centers. A partial responsibility income statement for a typical month is shown below: Profit Center B Profit Center A Profit Center C NCL - $ 70,000 Responsibility margins $ 200,000 $ 80,000 $ 50,000 Common fixed costs $ 165,000 $ 55,000 $ 55,000 $ 55,000 $ 15,000 Income from operations $ 35,000 $ 25,000 $ (5,000) After evaluating these data, NCL decides to close Profit Center B. This action eliminates all revenue, variable costs, and fixed costs traceable to Center B, but eliminates only $35,000 in common fixed costs. Closing Profit Center B has no effect upon the responsibility margins of Centers A income from operations 35,000 $ 25,000 $ (5.000) $ 15.000 After evaluating these data, NCL decides to close Profit Center B. This action eliminates all revenue, variable costs, and fixed costs traceable to Center B, but eliminates only $35,000 in common fixed costs. Closing Proht Center B has no effect upon the responsibility margins of Centers A and C. Closing Profit Center B should cause NCL's monthly operating income to: Decrease by $15,000. Increase by $5,000 Decrease by $20,000 O Decrease by $7,000