Due to concerns around single points of failure, a company decided to add an additional WAN to the network.
The company added a second MPLS vendor to the current MPLS WAN and deployed an additional WAN router
at each site. Both MPLS providers use OSPF on the WAN network, and EIGRP is run internally. The first site to
go live with the new WAN is successful, but when the second site is activated significant network issues occur.
Which of the following is the MOST likely cause for the WAN instability?


A. A changed CDP neighbor
B. Asymmetrical routing
C. A switching loop
D. An incorrect IP address