D. Olmec
Experts and historians believe that the Olmec civilization is the first great civilation of the mesoamerican. It si possible to find evidence of early instalments in the first half of the first century BC and its influence on Mayas and Aztecs is proven in many fields, like religion, social structures and other social aspects.
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B. Calendars
Some of the mayor evidence of an influence of the Olmec civilation on Mayas and Aztecs are in the structure and how the calendars appears to be fundamental in every aspects of the lives at the time. This makes sense considering the agricultural importance in those types of civilization, so the calendar and passing of time were of primarly importance in the social and cultural making of Olmec and later Mayas and Aztecs.
