Which One of the Following Statements About MRP Is Best

Which one of the following statements about MRP is best?

A) The fixed order quantity rule results in remnants.
B) MRP uses a level- by- level processing procedure; the component items are processed first.
C) An action notice should be issued if the scheduled receipt in a period is less than the projected on- hand inventory for that period.
D) The periodic order quantity rule introduces remnants that are used as a buffer against uncertainties.