I think they were protected by invaders
Explanation:
The Chinese government in order to curb the ever-growing population of china come up with a policy called the one-child policy in 1980.
The government viwed population to be growing rapidly and rapid growth would cause problems like unemployment, lack of resources, and hence, increase in criminal activities. The policy benefitted China and its population growth declined significantly over the years.
However, after 3 decades of the one-child policy, china saw a starking gender gap in its consensus. With only one child allowed people preferred male children over female. This caused an imbalance in the gender ratio. Moreover, the Chinese population started to age. The average from 28years to 39.6 years in three decades. With the increase in the numbers of old people, people in the working force started to decline.
Hence, recently in 2015 china repealed the one-child policy from all over its country. Although they allowed having two children now. "To improve the balanced development of population" – an apparent reference to the country's female-to-male sex.
Because people are picky on where they live
Europ, n to find more land
The answer is Factories.
New inventions in pieces of machinery make it more efficient for the company's owner to create a building structure that far different from the common cottage.
factories provide several features that do not exist in a cottage, such as waste pipe, Tall room in order to stack up inventories etc.
