Because there was a investment in industries other than agriculture
<span>Technological advancement.
With the likes of social media platforms like tweeter and facebook and specialist tech websites like techcrunch. The news of a new product will always spread virally especially if the product serves a niche purpose and it's relevant to solve a particular need that the market have been wanting for a long time. So, with improved technology that we have today, the news of new technology spreads easily.</span>
To grow larger and more powerful. They didn't have to pay people to work so they were able to keep to money and continue to buy more land and grow.
Option A is the right answer.
Began around 10,000 B.C, the Neolithic revolution in the history of Human marks the transition from small nomadic bands of hunter-gatherer to larger agricultural settlement and early civilization. People in the Paleolithic age used Primitive stone tools, whereas tools in the Neolithic era were more sophisticated. People during this age invented new types of tools such as sickle blades and stone axes etc. People in the Paleolithic age lived in small groups of 20- 30 people in caves, or in cabins made of tree branches, while, the Neolithic people with the advent of agriculture and raising cattle moved to settle as the farmers and villagers.