The level of inventory of a manufactured product has increased by 8,143 units during a period. The following data are also available: Unit manufacturing costs of the period Variable Fixed $14.00 $5.00 Unit operating expenses of the period 1.00 1.00 The effect on operating income if absorption costing is used rather than variable costing would be a Oa. $48,858 decrease Ob. $40,715 increase Oc. $40,715 decrease Od. $48,858 increase