Answer :
Arabian Peninsula's position is near to Africa and Asia completed their trade to a certain extent successful. Land trade increased prominence and caravan exchange turn out to be an essential share of the trading scheme. So the answer would be letter C.
Although the desert dominates most parts of the Arabian Peninsula, trade routes met at this place. 1,500 years ago when trade started growing in the region towns grew near the coast. Mecca was an initial example to this trend. If you pay close attention to the map, you'll see that major trade route combine Africa with the peninsula through India. Direction of the trade is also through this route. Therefore, the correct answer is C.