The largest city in Latin America is

Mexico city
Caracas
Rio-de-Janeiro
Buenos Aires

The correct answer is A. Mexico City.

Mexico City is the capital and most populous city of Mexico. It is located in the Valley of Mexico (Spanish: Valle de México), a large valley in the high plateaus of central Mexico, at an altitude of 2,240 meters (7,350 feet). The city has a population of 21.8 million, making it the most populous city in North America and the 20th-most populous city in the world.

Mexico City was founded in 1325 by the Mexica people, who later became known as the Aztecs. The city was originally called Tenochtitlan, which means “the place where the prickly pear cactus grows on the stone.” Tenochtitlan was a major center of the Aztec Empire and was one of the largest cities in the world at the time of the Spanish conquest.

After the Spanish conquest, Tenochtitlan was destroyed and rebuilt as Mexico City. The city became the capital of the Viceroyalty of New Spain, which was a Spanish colony in North America. Mexico City remained the capital of Mexico after the country gained independence from Spain in 1821.

Mexico City is a major cultural and economic center. The city is home to many museums, art galleries, and theaters. It is also a major financial center and is home to the Bolsa Mexicana de Valores, the second-largest stock exchange in Latin America.

The city is also a major transportation hub. Mexico City is served by two international airports, Benito Juárez International Airport and Toluca International Airport. The city is also served by a network of highways and railways.

Mexico City is a vibrant and cosmopolitan city with a rich history and culture. It is a popular tourist destination and is home to many world-famous landmarks, including the Palacio Nacional, the Catedral Metropolitana, and the Zócalo.

The other options are incorrect because they are not the largest cities in Latin America.

Caracas is the capital and most populous city of Venezuela. It is located in the northern part of the country, on the Caribbean coast. The city has a population of 2.2 million, making it the second-most populous city in Latin America after São Paulo.

Rio de Janeiro is the second-largest city in Brazil and the capital of the state of Rio de Janeiro. It is located in the southeastern part of the country, on the Atlantic coast. The city has a population of 6.7 million, making it the third-most populous city in Latin America.

Buenos Aires is the capital and most populous city of Argentina. It is located on the western shore of the Río de la Plata, on the South Atlantic coast. The city has a population of 15.3 million, making it the fourth-most populous city in Latin America.