The correct response is: The Mexica believed that the god Huitzilopochtli was leading them to a promised land.
The Mexica (or Aztecs) undertook a long migration based on a prophecy that their god Huitzilopochtli would guide them to a place where they would find an eagle perched on a cactus, eating a serpent, which ultimately led them to settle at Lake Texcoco.