Juniper Exam JN0-663 Topic 6 Question 66 Discussion

https://supportportal.juniper.net/s/article/MX-Example-Configuring-LDP-based-VPLS-using-primary-backup-for-redundancy?language=en_US

In LDP signaled VPLS, when you have a multihomed CE to two different PEs you can configure a neighbor and a backup neighbor in remotes PEs. In this case PE-1. If the VPLS is signaled with BGP then you have to configure the preference in PE-2 and PE-3. The spanning tree option mentioned in other comments needs the configuration of spanning tree in the CE and you also need to configure a l2control instance in PEs attached to the CE.