The correct answer is - urbanization.
The process of urbanization is the one associated with the growth and development of the cities. This process takes place when there's a growing population in a city, both caused by fertility rates and migration towards it, so the local authorities are making the peripheries of the cities and surrounding villages modernized and start to put institutions in them, as well as the necessary modern infrastructure.
I would say that the US and the Soviet Union at the end of WWII withdrew their troops as soon as a demilitarized zone was created. Also, I am sure they would require a peace treaty to be signed with Germany before withdrawing troops.
Answer:
Iraq war that happened ages ago search on the Internet for more details
Temperature and precipitation
