A router learns a prefix from iBGP (AD 200) and from EIGRP external (AD 170). Which route will the router place in the RIB?

The router will install the EIGRP external route (AD 170) into the Routing Information Base (RIB). This is because routers prioritize routes based on their Administrative Distance (AD), with lower AD values indicating higher trustworthiness. Since EIGRP external has an AD of 170, and iBGP has an AD of 200, the EIGRP route is preferred. iBGP routes (AD 200) are less preferred than EIGRP external routes. Load balancing only occurs if multiple paths to the same destination have the same AD and metric, which is not the case here. The prefix length is used to select the most specific route when multiple routes to the same network exist, but AD is evaluated first when comparing routes from different routing protocols.