Right answer:
A. Andes
Medellín, a city located in Colombia, a south american country, and the capital of the department of Antionquia, is the second-largest city in this country. This city is located in the Aburrá Valley, a central region of the Andes Mountains in South America. The longest continental mountain range in the world are Los Andes and form a continuous highland along the western edge of South America.
