Answer:
Because the region along the Huang River provided what was needed for agriculture: fertile land and water.
Step-by-step explanation:
The early Chinese settled in the fertile lands of the Huang River, composed of a sediment brought and deposited by the waters, over millennia of the highlands of central China and the winds coming from the deserts to the west. In this irrigated land, the Chinese cultivated millet, vegetables and native fruits, especially along the upper and middle course of the river. In the lower sector of the Huang River, they cultivated rice. During the third millennium a. C., surplus production favored the establishment of permanent villages, and by the middle of that millennium there was almost a continuum of settlements and towns along the river, outlining a principle of civilization.