Route lists determine the order of preference for route group usage. If a route list is configured, what is the minimum number of route groups that you must configure?

A route list in CUCM requires only one route group to be valid and functional, because the route list's role is to define a prioritized sequence of route groups - a single route group satisfies this requirement and allows calls to be routed through the associated gateways or trunks.

Two route groups are not required; a second group is optional and typically added only for failover or load balancing, not as a minimum.

Three route groups exceed the minimum; they may appear in complex multi-site failover designs but are not mandated.

Four route groups are not required and reflect an unsupported assumption about CUCM minimum configuration.

Five route groups are not required; the minimum is one, and higher counts are purely optional for redundancy.

Six route groups are not required; this exceeds the minimum by far and is not a CUCM configuration baseline.

Seven route groups are not required and would be an atypical, non-minimum configuration.

Eight route groups are not required; the minimum is one, and this number far exceeds any baseline requirement.