A customer wants to merge two DS-24M2 switches which are 20km apart using DWDM. They will
use port 0 on both switches for the long distance ISL. What is the best way to set up the switches?

A.
Set port 0 on both switches to 2 Gb/s

B.
Set port 0 on both switches to 1 Gb/s

C.
Set port 0 on both switches to 2Gb/s with 20 BB_credits

D.
Set port 0 on both switches to 2Gb/s with 40 BB_credits