The correct answer is that the Native Americans were dying off in large numbers because of the diseases that were in the places they were working in. Hope this helps.
The three returns that foreigners would receive from the Chinese emperor for kowtowing and giving tributes were:
<span>.The right to trade in the capital ,recognition of their ruler and the right to receive tribute in return.</span>
Kowtowing was the act of bowing for the royalty, in the imperial court, while tributes were goods brought in terms of gifts to the emperor.
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