Which is not an example of cultural diffusion in the united states?

eating a hotdog at a barbeque
going to a sushi restaurant
attending a live opera event
taking a latin dance class

Eating a hot-dog at a barbecue

Explanation:

The cultural diffusion is a process in which people from different cultures, races, ethnic groups, are adopting certain things into the culture, be it because they like them, being advantageous, more modern, fun etc. This has been enabled on a much larger scale with the process of globalization, so the rate of cultural diffusion in the past century has constantly been increasing. In the examples we have, the sushi restaurant is a Japanese trait but it is used in the US, thus it is part of cultural diffusion, so is the opera event which is an Italian product, and the Latino dance class is part of the Latin American culture. The hot-dog though would not be part of the cultural diffusion, as the modern version of the hot-dog is an American invention, not something imported and adopted from abroad.