Answer:
the answer is the fist one I think
• the Americas were less densely woven than in the afro-Eurasian region. There was no equivalent to the silk, sea, or sand roads. • Spread of agricultural products was slower and less pro owned on the Americas • Spread of distinct cultural traditions like Buddhism, Christianity, or Islam · Americas did have zones of interaction • River networks of North America, where commerce plays an important role in regions where contact was possible, the dense communication lays between rather than within the regions that housed the two great civilizations of the Western Hemisphere- mesoamerica and the Andes.
Tariff reduction is the the reduction of taxes on an item being shipped to another country. The answer is the last one. Birth and death rate directly causes population growth or decline. Migration can help people thrive in an environment which means more population. I hope this helps!