A metric is ___

a. When a router obtains a clear view of the routes in a network.
b. A numeric measure assigned to routes for ranking the routes best to worst; the smaller the number, the better.
c. A procedure in the protocol that enables routers to use any of the multiple data paths available from multiple routers to reach the destination.
d. A procedure in the protocol that determines the best route.

b. A numeric measure assigned to routes for ranking the routes best to worst; the smaller the number, the better.
Explanation:
Item Issue Purpose
1 Path Determination A procedure in the protocol that determines the best route.
2 Metric A numeric measure assigned to routes for ranking the routes best to worst; the smaller the number, the better.
3 Convergence This happens when a router obtains a clear view of the routes in a network. The time it takes for the router to obtain a clear view is called the convergence time.
4 Load Balancing A procedure in the protocol that enables routers to use any of the multiple data paths available from multiple routers to reach the destination.

Metric applies only when comparing routes of the same routing protocol (that is, administrative distance), so if the same route is learned via two different routing protocols, the route with the better administrative distance would be installed into the routing table.