What do the traffic received and sent statistics present?

Refer to the exhibit.

A user logged in to the Self-Service Portal as shown.

What do the traffic received and sent statistics present?
A . the total amount of the traffic the quest transmitted, as seen through RADIUS CoA packets from the client to ClearPass
B . the total amount of traffic the guest transmitted, as seen through RADIUS accounting messages sent from the NAD to ClearPass
C . the total amount of traffic the guest transmitted, as seen through RADIUS CoA packets from the NAD to ClearPass
D . the total amount of traffic the guest transmitted after account expiration, as seen through RADIUS accounting messages sent from the NAD to ClearPass
E . the total amount of traffic the NAD transmitted to ClearPass, as seen through RADIUS accounting messages from the NAD to ClearPass.

Answer: B