An auditor desires to determine if purchase invoices were properly approved for a population of 12,000 purchases processed during 20x4. The auditor wishes to design a sample that will give 95 percent confidence that the error rate did not exceed 0.5%. The expected deviation rate is 4 percent. Which form of sampling would be most appropriate for this application? O Stop or go attribute sampling O Fixed sample size attribute sampling Discovery attribute sampling O Mean-per-unit variable sampling