The correct answer is - D. Farms could support larger groups of people, which led to increased population growth.
Alongside the rivers farming took on a step up in the production of food. The rivers were flooding each year and with it they were making big deposits of fertile material around them. This meant that the soil was of great quality each year and the people that were living there were able to produce big amounts of food, very often even surplus of food. This allowed the river valley civilizations to be able to prosper and also focus on other things apart from sheer survival, so cities started to emerge, the architecture started to develop, the basis of sciences etc.
the national assembly promise at the tennis court oath not to separate, and to reassemble wherever circumstances require, until the constitution of the kingdom is established. Hope it helps
