Final answer:
Traders from places such as India and Egypt came to Chang'an, the Tang capital, to conduct business, which supports the research on China as a trading giant under the Tang dynasty.
Step-by-step explanation:
The fact that best supports Wendell's research on China during the Middle Ages as a trading giant under the Tang dynasty is that traders from places such as India and Egypt came to Chang'an, the Tang capital, to conduct business. This demonstrates that Chang'an was a hub for international trade during the Tang dynasty, attracting traders from distant regions. The presence of foreign traders in a Chinese city indicates that China had a flourishing trade network and was considered a major trading power.
Learn more about China's trade during the Tang dynasty