The Swahili City States were trading states along the east coast of Africa, from Kenya to Mozambique. They provided and connected African raw material to the rest of the Indian Ocean world-Arabia, India, Persia, and China.
They lived in agricultural villages and produced items for small-scale regional economies. Then, around 1000 CE, The Indian Ocean started packing with trade ships running from the Red Sea to India to China.
Sailing techniques at the time didn't allow for open-ocean sailing, so merchants hopped along the coast, and those little villages found themselves in an ideal location. As trade increased, the villages became prosperous and larger, dominated by an elite class of merchants as the Swahili language and cultural identified was solidified.
For those reasons, between the options presented the one that match with the Swahili trading cities is India, letter B.
