Which of the Following Best Explains an 'Order-To-Pay' System

Multiple Choice

Which of the following best explains an 'order-to-pay' system? 

A)  A system allowing project support staff to order materials and services using the company's corporate purchasing agreements. 
B)  A system allowing orders to be placed with any supplier. 
C)  A cash ordering system. 
D)  A system where project support staff pay for their own orders then claim the expenditure back from their employers.