Which of the Following Best Explains an E-Procurement System

Which of the following best explains an e-procurement system? 

A)  A system which enables authorized users within organizations to order directly from an electronic catalogue without the interference of a purchasing department. 
B)  A system which enables authorized users within organizations to order directly from a purchasing department. 
C)  A system which enables authorized users within organizations to order directly from a purchasing department who then us an electronic catalogue. 
D)  A system which enables anyone to order directly from an electronic catalogue without the interference of a purchasing department.