Which two overlay network design considerations must be made for a Cisco SD-Access network? (Choose two.)

An existing network solution is using BFD in echo mode. Several of the network devices are experiencing high CPU utilization which an engineer has determined is related to the BFD feature. Which solution should the engineer leverage to reduce the CPU load?

A company's security policy requires that all connections between sites be encrypted in a manner that does not require maintenance of permanent tunnels. The sites are connected through a private MPLS-based service that uses a dynamically changing key and spoke-to-spoke communication. Which type of transport encryption must be used in this environment?

Which protocol is deployed through LAN automation to build node-to-node underlay adjacencies in SDA?

Refer to the exhibit.

An engineer must optimize the traffic flow of the network. Which change provides a more efficient design between the access and the distribution layer?