When two routes to the same destination are learned from different routing protocols, which attribute determines which route is installed?

Administrative distance (AD) is the first criterion used by a router to determine the best path when multiple routing protocols provide routes to the same destination. Each routing protocol is assigned a default AD value (e.g., EIGRP has 90, OSPF has 110, RIP has 120). The route with the lowest AD is preferred and installed in the routing table. The dual algorithm is a component of EIGRP, not a general mechanism for comparing routes from different protocols. Metric is used by a routing protocol to determine the best path within that protocol, but AD takes precedence when comparing routes from different protocols. Hop count is a specific type of metric used by some protocols like RIP, but it's not the primary tie-breaker across different protocols.