Right answer: Maya
The zero as we know it today, was found in India and arrived to Europe through the Arabs with the invasion of what we know today as Spain.
However, the zero was also known by some pre-Columbian civilizations, among them the Mayans (although there are theories that claim that they could have been the Olmecs, a civilization before the Mayans, but until now there is not enough information to confirm it).
The Mayan numbering system is considered as a fairly complete mathematical one. This was due to the fact that it was a civilization with a high knowledge of astronomy and calendars, hence, they needed a symbol that represented nothingness. For this reason, long before being colonized by the spaniards, the Maya civilization created the zero and adapted it to their needs.
Nevertheless, it should be noted that it is known that it was several years ago B.C. when the Babylonian scribes conceived a sign that represented the void, that is, the absence of number. This being considered as a vestige that this civilization already conceived the idea of something that represented nothingness.
In summary, the practice of using the zero symbol spread across Europe. But the Mayans, located on the other side of the ocean, in a continent cut off from the others known until that moment, discovered the use of zero by their own means.