the answer to this is c i hope i helped
Your ending the trade of slaves and ending slavery would be ending owning a slave at all.
Your answer would be population density.
The word "unique" means something that is unlike anything else. In urban areas, it's mostly heavily populated due to the amount of residential, business, and suburban areas. Urban areas are packed with houses, apartments, businesses, and etc. When you go into the country side of town, they're not heavily populated due to it being mostly land and not residential places.
Crusades were a series of 9 military expeditions which sought to recapture Jerusalem and other places sacred to Christianity from the Muslims. They were formally launched by Pope Urban II in the late 11th century to help the Byzantine Empire against the Seljuk Turks.