How did physical geographic factors such as River valleys and human geographic factors such as the development of agriculture and cities encourage the development of River valley civilizations

The geographic factors of rivers and valleys provided good farm lands, which made more food to support the growing population. ... The rivers flooded in the spring, which left behind mud that enriched the soil. The good farming conditions caused an increase in food, which helped the population grow.

the navigation act prevented the colonies from exporting to countries other than britain and it prevented the importation of goods by other countries as well. so i believe the correct answer is d. other nations could not deliver goods to the colonies.

hope this .