I. over 200 languages were spoken in north america. ii. between 2 and 7 million native americans lived in north america. iii. each native american tribe participated in a unique culture. all of the above characteristics describe what north america looked like a. before native american tribes practiced agriculture b. after early humans crossed the bering land bridge c. just prior to native american and european contact d. during the last major ice age

B. after early humans crossed the Bering Land Bridge

Explanation:

Americans who hiked over a “land bridge” from Asia to what is now Alaska more than 12,000 years ago. In fact, by the time European adventurers arrived in the 15th century A.D., scholars estimate that more than 50 million people were already living in the Americas. Of these, some 10 million lived in the area that would become the United States.

answer; native americans who sometimes actively impeded railroad construction; physical obstacles like rivers and canyons, and