There teaching, the way they teach there students, in other countries they have more advanced teaching. P.S this is just my reasoning there are plenty other answers to this question.
The answer is C. Natural sources are limited. People tend to get their resources from the environment in order to live and survive. Because of the increasing number of human population, resources become scarce and there is not enough supply for consumption in the near future.
1-Better land degradation
2-Causes more invasive species
