Because of cultural reasons
Answer is the united states
Answer:
Erosion can cause water in the rivers to become heavily polluted. The water might carry pesticides, heavy metal ions and other toxic wastes. When this water will be used for irrigation purposes, the growth of plants will be heavily affected by them.
When humans use water this contaminated water from the rivers, it will led to many diseases in humans. Also, the wild- life animals which depend on this river might take in toxic compounds due to which they might die.
Oil is one of Saudi Arabia's major exports.
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).