<span>D. Overcrowding and destruction of rain forests</span>
Answer:
2
Explanation:
3 is physical 4 is as well so it has to be 1 or 2
Hello
Four major types of landform are-:
*Maontain
* pleatue.
*Plains
*Hills.
Thanks
Explanation:
Given the importance of oxygen for animals, researchers suspected that a sudden increase in the gas to near-modern levels in the ocean could have spurred the Cambrian explosion. ... This supported the idea of oxygen as a key trigger for the evolutionary explosion.
