The correct answer is C. Cultural diffusion.
Step-by-step explanation
Cultural diffusion is a characteristic of human communities in which cultural, philosophical, or religious traits are transmitted to other communities by different means such as oral and written tradition. Also, cultural diffusion can be evidenced when there are relationships between two communities. An example of this phenomenon is the spread of Buddhism originating in India to China because both countries were part of the Silk Road, a road that connected Asia and Europe and where merchants from different origins were transported. Therefore, the correct answer is C. Cultural diffusion.