The correct answer is 1, 3, & 4, because they represent North America, Africa, and Europe, respectively. (These continents are often placed in a historical context as "The Atlantic World.") The system, which existed during the era of mercantilism, saw slaves sent from Africa to the Americas, raw goods sent to Europe, and manufactured goods- such as guns and liquor- sent to Africa. Historians often include South America in the system, but that is not a choice here.