L Curtis, a Maintenance Supervisor, Submitted Maintenance Invoices from a Phony

Multiple Choice

L. Curtis, a maintenance supervisor, submitted maintenance invoices from a phony repair company and received the checks at a post office box. This should have been prevented by

A) comparison of the company name to the approved vendor list by the check signer.
B) recognition of the excess maintenance costs by Curtis's supervisor.
C) refusal by the purchasing department to approve the vendor.
D) All of the these choices are correct.