AS111 wants AS200 preferred for 172.20.5.0/24 and AS100 as backup. AS100 became unused for all routes after applying the route-map. Which configuration fixes the issue?

The correct configuration fixes the issue by adding a permit 20 statement to the route-map. Without this explicit permit statement, the implicit deny at the end of the route-map would cause all routes not matched by permit 10 (i.e., all routes other than 172.20.5.0/24) to be denied. This is why AS100 became unused for all routes. The permit 20 statement ensures that all other routes are permitted to pass through the route-map without any modifications, allowing AS100 to be used as a backup for other routes. The incorrect options either modify the local preference incorrectly or apply the route-map in the wrong direction or to the wrong neighbor. Setting local preference to 110 for the specific prefix would make it preferred, but the core issue of other routes being denied remains. Applying the route-map out would affect routes advertised from AS111, not routes received by AS111.