I think it’s d bc the rest is based on your knowledge
Crust:outer silicate solid crust
mantle:highly viscous
core:solid inner core
This is called species richness
Answer: A. Increasingly crowded urban areas
Explanation: Think about it this way. If you heard about more products being made in a city that means what? More jobs! Many people moved to cities and then made the cities unsanitary and many diseases spread around such as hepatitis. Anyways the more jobs there was the more money people could make and the more people lived in big cities like New York.
The correct answer for the given question above would be option B. The essential aspect of geography that you would learn about the creation of mountains would be physical systems. The physical systems of geography is also known as physical geography. Physical geography is the scientific study of the natural features of the Earth's surface.
