As shown in the figure, all devices operate in the MPLS network. The downstream switch SWA finds the label mapping message of 1.1.1.1 to the SWB. The SWB receives the label distributed by the downstream switch SWA and then distributes the label to the SWC. The SWC receives the label sent by the SWB. Then send it to SWB to send the label.
Then, what are the label control mode and the label distribution mode in the network respectively?
A . Ordered+DU
B . Ordered+DoD
C . Independent+DU
D . Independent+DoD
Answer: A