During a purchases test, in which the auditor is checking that a sample of 25 purchase invoices have been stamped with evidence of goods received, the auditor discovers that one invoice with a value of $7 has no such evidence. What should the auditor do next? Please select the right answer. Sorry, your answer was not correct! Perform additional tests of control on purchases Disregard the error as immaterial and form a conclusion on the basis of the other 24 invoices Extend the sample and inform the client of the error found in the report to management Request an explanation from the client and establish if the error is an isolated incident