Answer:
Correct answer is they called themselves the people of Middle Earth .
Explanation:
First option is not correct as they knew about the existence of this civilizations, especially the Indian, as they have traded with them a lot.
Second option is correct as they believed they were living in the center of the world, and that the natural barriers are dividing them from the rest of the world.
Third option is not correct as the Huang River was were the civilization developed.
Last option is not correct as this has nothing to do with their beliefs about their location.