Why were the Aztecs able to take control of the basin known as the Valley of Mexico?

Read what our textbook says about this for help!

"One of these basins- the Valley of Mexico- was the center of the Aztec empire. Fertile volcanic soils and water flowing from the mountains around it made the valley a good place to settle. At the center of the Valley of Mexico was a large lake, Lake Texcoco. The Aztec could easily defend their city from attack. The lake itself and the canals the Aztec built made transport easy. " (World Geography, page 170)

(1 point)

They produced goods that made them wealthy

They built a strong defense that protected Lake Texcoco from invasion

They were the second people to settle in the area and create cities there

The correct answer is:

They built a strong defense that protected Lake Texcoco from invasion