D. All of the above.
Explanation - An organism has encountered reproduction, getting energy and staying healthy as their challenge. Limiting factor plays an important role in this. When the amount of limiting factor is sufficient then different organisms try to grow and reproduce but here the competition between the species arise.
Different species need to compete with each other for their food, growth and reproduction. The species that is unable to sustain itself in the amount of limiting factor available tends to get extinct.
