Which two options can you use to configure an EIGRP stub router? (Choose two)

An architect is designing a network that will utilize the spanning tree protocol to ensure a loop-free topology.
The network will support an engineering environment where it is necessary for end users to connect their own network switches for testing purposes. Which feature should the architect include in the design to ensure the spanning tree topology is not affected by these rogue switches?

Refer to the exhibit.

An architect must design an IP addressing scheme for a multisite network connected via a WAN transit. The campus site must accommodate 12,000 devices and the branch sites must accommodate 1,000 devices. Which address scheme optimizes network device resources, contains convergence events to the different blocks of the network, and ensures future growth of the network?

Refer to the exhibit.

An engineer is designing a BGP solution for a client that peers with ISP1 for full Internet connectivity and with ISP2 for direct exchange of routes for several third parties. Which action, when implemented on the edge routers, enables the client network to reach the Internet through ISP1?

Refer to the exhibit.

Area 10 is a regular OSPF area and networks 10.1.1.0/24 and 172.16.1.0/24 are internal. Which design provides optimal routing between both networks when the link between routers C and E fails?