The correct answer is - Olmec.
The Olmec civilization was existing in the period between 1,200 BC up until 400 BC. This civilization developed in Mexico, more specifically in the south-central lowlands of the country. The Olmec were a very advanced civilization for their time, and they are considered as the civilization that set the basis for all the others civilizations in Mesoamerica, like the more ''famous'' Maya and Aztec civilizations. The trademark of the Olmec is the big stone heads, about which there's lot of debates about their purpose and means.