What are three key design principles when using a classic hierarchical network model? (Choose three.)

Refer to the exhibit.

This new OSPF network has four areas, but the hub-and-spoke area experiences frequent flapping. You must fix this design failure. Which two mechanisms can you use to isolate the data center area from the hub-and-spoke area without losing IP connectivity? (Choose two.)

An MPLS service provider is offering a standard EoMPLS-based VPLS service to Customer A, providing Layer 2 connectivity between a central site and approximately 100 remote sites. Customer A wants to use the VPLS network to carry its internal multicast video feeds, which are sourced at the central site and consist of 20 groups at 5 Mb/s each. Which service provider recommendation is the most scalable?

You are the lead network designer hired by Service Provider XYZ to deploy CoS functionality on
the core MPLS network (P routers). The goal of the network design is to provide a complete CoS
solution to all customers that purchase services such as dedicated Internet access, MPLS L3VPN,
and L2VPN (pseudowire). Service Provider XYZ has these design requirements:
-The network supports four service queues with equal treatment for delay, jitter, and packet loss.
-Queues are numbered 0-3, where 0 is the default queue.
-Three queues have one treatment.
-One queue has either one or two treatments.
If your design includes eight CoS queues on the Service Provider XYZ MPLS PE router ingress
(CE facing) interface, how will customer traffic be classified as it enters the MLS P routers?

Your company experienced a number of network incidents that had a significant impact on business operations. Because a root cause cannot be identified, your CTO asks you to help the network management team implement the FCAPS framework. On which two areas would you provide guidance to the network management team? (Choose two.)