For effective internal control, the accounts payable department generally should:

A$.$ Stamp, perforate, or otherwise cancel supporting documentation after payment is mailed.

B$.$ Ascertain that each requisition is approved as to price, quantity, and quality by an authorized employee.

C$.$ Obliterate the quantity ordered on the receiving department copy of the purchase order.

D$.$ Establish the agreement of the vendor's invoice with the receiving report and purchase order.