Tracing Copies of Computer-Prepared Sales Invoices to Copies of the Corresponding

Tracing copies of computer-prepared sales invoices to copies of the corresponding computer-prepared shipping documents provides evidence that

A) Shipments to customers were properly billed.
B) Entries in the accounts receivable subsidiary ledger were for sales actually shipped.
C) Sales billed to customers were actually shipped.
D) No duplicate shipments to customers were made.