31.An auditor is considering whether the omission of a substantive procedure considered necessary at the time of an audit may impair the auditor's present ability to support the previously expressed opinion. The auditor need not apply the omitted procedure if the

a.Financial statements and auditor's report were not distributed beyond management and the board of directors

b.Auditor's previously expressed opinion was qualified because of material misstatement in the financial statements

c.Results of other procedures that were applied tend to compensate for the procedure omitted

d.Omission is due to unreasonable delays by client personnel in providing data on a timely basis