Default routes are to route packets that are destined for networks not listed in the routing table. Also, default routes are ideal for use in stub networks. Stub networks are those that have only one adjacent router interface and therefore only one interface to send any packet, regardless of destination. When used in this fashion the default route will be the only route in the routing table.

The following statements are also true of default routes:
* A default route is also known as the gateway of last resort.
* The default route in Internet Protocol Version 4 (IPv4) is represented as 0.0.0.0/0.

The option stating that default routes are used to route packets destined only for networks that are listed in the routing table is incorrect. Default routes are used for routing packets that are destined for networks not listed in the routing table.

The option stating that default routes should not be used in a stub network is incorrect. Default routes are helpful in topologies where it is not necessary to learn specific networks, making them ideal for use in a stub network.

The option stating that network security is increased by using default routes is incorrect. Default routes are not concerned with enhancing network security.