1.[单选题]The metric assigned to each network depends on the type of protocol.Some simple protocol, like RIP, treats each network as equals.The (1) of passing through each network is the same;it is one (2) count.So if a packet passes through 10 network to reach the destination, the total cost is 10 hop counts.Other protocols, such as OSPF, allow the administrator to assign a cost for passing through a network based on the type of service required.A (3) through a network can have different costs(metrics).For example, if maximum (4) is the desired type of service, a satellite link has a lower metric than a fiber-optic line.On the other hand, if minimum (5) is the desired type of service, a fiber-optic line has a lower metric than a satellite line.OSPF allow each router to have several routing table based on the required type of service.