The civilizations that influenced both the Maya and Aztec civilizations are primarily the Olmec civilization. The Olmecs, often regarded as the "mother culture" of Mesoamerica, laid the groundwork for many cultural, artistic, and religious practices that were later seen in both the Maya and Aztec societies. These include aspects like monumental architecture, ritual ball games, and certain deities.
The other civilizations listed (Hohokam, Inca, and Indus) did not have a direct influence on either the Maya or Aztecs in the same way the Olmecs did.
- Hohokam: A culture in what is now the Southwestern United States, known for their canals and agriculture, but not a direct influence on Mesoamerican cultures.
- Inca: A South American civilization that developed independently of the Maya and Aztecs and is known for its distinct language, agriculture, and architecture.
- Indus: An ancient civilization located in South Asia, which is also unrelated to the Mesoamerican cultures.
Thus, the Olmec civilization is the correct answer regarding influences on both the Maya and Aztec civilizations.