Answer:
<u><em>River valley civilizations</em></u>
Explanation:
They were centred around various river valleys as their main source of livelihood and the flourished only due tiote river valley on which they were based. Like the harappan in Indus Valley, The yellow river (Huang He), the Mesopotamia around Tigris and Euphrates and the egyptian Nile.
A farmer would choose to live in this area most likely because the land in here has many agricultural advantages that can be utilized for farming. Also, these lands are known to be the most fertile in that area. Flooding also helps in preventing weeds and keeping the soil healthy.
