An organism? There is nothing past organ systems
Liquid water, which is necessary for life as we know it, continues to exist on the surface of Earth because the planet is at a distance, known as the habitable zone, far enough from the Sun that it does not lose its water to the runaway greenhouse effect.
I would say C! Most developing countries have high birth and death rates, while developed countries are more steady.
These are the most common symptoms associated with PSTD
The limbic system is responsible for controlling learning and emotional behavior
