Final answer:
The spread of higher-cost specialty coffee shops across the United States in the 1990s exemplifies contagious diffusion.
Step-by-step explanation:
The spread of higher-cost specialty coffee shops across the United States in the 1990s is an example of contagious diffusion. Contagious diffusion refers to the spread of a cultural trait or trend through direct contact or proximity between individuals or places. In this case, the trend of specialty coffee shops spread from one location to another through word of mouth, social networks, and the desire for unique and high-quality coffee experiences.
Learn more about contagious diffusion