C
Test question analysis: Based on the knowledge learned, it can be seen that due to the relatively open foreign policy implemented by the ruling class and the development of external transportation, the economy of the Tang Dynasty , culture was in a leading position in the world, which prompted the Tang Dynasty's foreign exchanges to become more frequent than ever before. Chang'an in the Tang Dynasty was not only the center of exchanges between various ethnic groups at that time, but also an international metropolis. The fundamental reason for the prosperity of the Tang Dynasty's foreign trade was the Tang Dynasty's economic prosperity and strong national power. Therefore, option C is selected.
Comments: The Tang Dynasty had a unified country, strong national power, prosperous economy, and prosperous culture. It was the most advanced, civilized, and powerful country in the world at that time. Countries around the world admire and yearn for Chinese culture, especially Eastern countries. They regard China as the "base camp of Eastern culture." Muhammad, the founder of Islam, encouraged his disciples that "even if knowledge is far away in China, you should still seek it." The Japanese people have "endless yearning for Chinese culture" and hope to "live a splendid cultural life like the Han people." The prosperous Tang Dynasty has become synonymous with China in the minds of people from all over the world, and people still call Chinese people Tang people.