Which One of the Following Is of the Least Concern

Multiple Choice

Which one of the following is of the least concern to the auditor when designing substantive tests of transactions for the sales/collection cycle?

A) Sales being included in the journal for which no shipment was made
B) Sales to related parties, such as officers and subsidiaries
C) Sales recorded more than once
D) Shipments being made to nonexistent customers and recorded as sales