What is the AD value of the route O 192.168.4.0/24 [110/3] via 10.0.12.2?

The Administrative Distance (AD) is a value that routers use to rank the trustworthiness of routing information received from different sources. Each routing protocol has a predefined AD value, which allows the router to choose the best path to route packets when multiple routes to the same destination exist.

In this case, the route O 192.168.4.0/24 [110/3] indicates that the route is learned through an OSPF (Open Shortest Path First) protocol, which has a default AD value of 110. The format [110/3] means that the AD is 110, and the 3 represents the metric that OSPF uses to determine the best path.

Thus, the correct answer highlights that the AD of the route is 110, which is consistent with the established default for OSPF. Understanding AD values is crucial for network design and troubleshooting, as it helps in determining how routing decisions are made in a mixed network environment.