The creation of approximately ten million refugees from 1947-48 was a result of World War II.
World War II brought destruction of lot of countries, millions of people lost their homes that were flattened with the ground, the economies were destroyed and on the verge of bankruptcy, so millions of people left their countries in search for better life (or rather just normal life).
The soil layers are, in order: dirt, humus, rock. So the answer is D.
Czech Republic and Slovakia
Everyone who's eighteen y/o or above have a right to vote in Ghana