Which of the following statements is true regarding assertions in the revenue cycle? a. The allowance for doubtful accounts has important implications for the ownership assertion of accounts receivable. b. Audit evidence about the existence of revenues is also the most appropriate evidence about the valuation of receivables. c. It is typical that all five assertions for revenue are equally important. d. If a client has an incentive to overstate revenues, the existence assertion would be more relevant than the completeness assertion.