Which of the choices below is an example of an exterior gateway protocol (EGP)?

Border Gateway Protocol (BGP) is the correct answer as it is specifically designed to facilitate the exchange of routing information between different autonomous systems on the internet. An exterior gateway protocol operates outside the confines of a single organization's network and is responsible for routing data across the various interconnected networks that comprise the global internet.

BGP is crucial for the function of the internet as it manages how packets are routed between these autonomous systems using path vector mechanisms. It takes into account various factors including policies and rules set by network administrators to choose the best path for data to traverse. This makes it a vital protocol for internet service providers and large organizations managing multiple connections.

In contrast, the other protocols listed are classified as interior gateway protocols, which are used to route data within a single autonomous system or between networks under a single administration. Open Shortest Path First (OSPF), Routing Information Protocol (RIP), and Interior Gateway Routing Protocol (IGRP) are primarily used in local or enterprise networks rather than for communication between different organizations or providers.