The correct statements about how the shift to farming affected Native American cultures are:
- Farming encouraged native cultures to build more permanent shelters and communities.
- Agriculture provided a surplus of food, allowing for an increase in the population.
The other statements are not accurate. The shift to agriculture generally did not lead to a boost in immunity from diseases, and while farming could lead to land competition, the idea that it caused civilizations to wither away is an oversimplification and not universally applicable.