L3 switches R1 and R2 are in the backbone of the network. They are connected by a routed EtherChannel bundle consisting of eight Gigabit Ethernet ports. The routed link is represented as subnet X.0 in the diagram. Since X.0 is routed, it is not a VLAN trunk. How can spanning tree loops be prevented in the backbone of this network?
A.
Since EtherChannel X is routed there are no spanning tree loops.
B.
Configure seven of the eight ports in the bundle as passive interfaces
C.
Configure UplinkFast on R1 and R2
D.
Disable Spanning Tree Protocol (STP) on R1 and R2
E.
Disable VLAN X on seven of the eight ports in the bundle