The correct answer is - As Buddhism spread, it incorporated ides from local cultures.
The Buddhism is a teaching that first appeared in India. Ironically enough, it is not practiced in India nowadays. Through the trade routes, the Buddhism spread eastwards on the territories of East Asia and Southeast Asia.
As it was spreading and gaining on popularity in different places where people had different cultures, the Buddhism mixed with the local traditions and beliefs. That led to variations of the Buddhism from place to place, and that can also be easily seen in the art, where the statues of Buddha are created in accordance to the local style and traditions.