Which of the following reflects the effect of the year-end adjusting entry to record estimated uncollectible accounts expense using the allowance method? assets = liab. + equity rev. exp. = net inc. cash flow a. − = na + − na − = − − oa b. na = − + − na + = − na c. na = − + − na + = − − oa d. − = na + − na + = − na