Final answer:
The overall increase in agricultural production by 950 CE was primarily driven by advancements in agricultural technology, including the development of quick-ripening rice and improved irrigation, which led to increased availability of arable land and produce.
Step-by-step explanation:
By 950 CE, the chief factor contributing to an overall increase in agricultural production was the improvements in agricultural technology.
Significant advancements included new strains of quick-ripening rice that allowed for two harvests in a single year and enhanced irrigation techniques, such as chain-driven pumps that converted unused hillsides into arable land.
Together with government actions to stabilize agricultural markets and food prices, these technological advancements led to more land being farmable, an increase in harvests, and greater availability of produce. This increase in production supported a considerable expansion in population and urbanization, with rural farming households gaining increased purchasing power.