Why is this?

There is a recommended order to powering up the IP Office 500 V2: first up the expansion modules before powering up the control unit.

Why is this?
A . It is easier to start with the expansion unit at the top and then work your way down.
B . All expansion units need to be powered for the control unit to discover them.
C . The expansion units may not always see the control unit if powered up last.
D . The expansion units take longer to power up.

Answer: B

Explanation:

References: https://downloads.avaya.com/elmodocs2/ip_office/R4.2/Newissuesept08/eng/ip_office_inst allation.pdf Page: 111