The correct answer is C. Lowest administrative distance. When a switch learns multiple possible routes to the same destination, it must select the preferred or best route to install and use for forwarding. HPE Aruba Networking documentation explains that administrative distance is one of the main criteria used to determine the preferred route when multiple paths exist to the same destination. The route with the lower administrative distance takes precedence. This is why connected routes, static routes, and dynamically learned routes can be preferred differently depending on their administrative distance values. Option A is incorrect because a default route is used only when no more specific route exists. Option B is incorrect because a static route is not automatically selected merely because it is static; it is preferred only if its administrative distance and route specificity make it the best candidate. Option D is incorrect because the highest administrative distance is less preferred, not more preferred.