Answer: 4)They understood the concept of zero.
Step-by-step explanation:
When the Mayans discovered the concept of zero around two millennia ago, the rest of the world had not with only the Mesopotamians having used it way earlier.
This means that the Mayans started using the concept of zero around a thousand years before the Europeans who only started using it thanks to interactions with Asians.
Knowledge of the concept helped the Maya perform more precise calculations by using zero as a placeholder.