Answer:
D.a series of ancient trade routes that connected China with Europe and East Africa
Step-by-step explanation:
The answer is D because it was a trade route connecting China, Europe, East Africa during the 130 b.c it was used for trading such as gold, silver, and many more. There's was a problem with the silk road because the first geography route was complicated and most of the passages they traveled on were narrow and somewhat dangerous, There's was also diseases spreading such as chicken pox, Measles.
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