The level of inventory of a manufactured product has increased by 7,838 units during a period. The following data are also available: Variable Fixed Unit manufacturing costs of the period $14.00 $3.00 Unit operating expenses of the period 2.00 2.00 The effect on operating income if variable costing is used rather than absorption costing would be an) Oa. $23,514 increase Ob. $23,514 decrease Oc. $39.190 increase Od $39,190 decrease