Answer: C. Miller and Urey showed that inorganic compounds could combine to form the building blocks of living cells.
Explanation:
The Miller and Urey were the two scientists who created the atmospheric conditions that were expected to be present on primitive earth. They demonstrated that several organic compounds have been formed spontaneously from the inorganic compounds like water, ammonia, methane and others.
The exposure of mixture of inorganic compounds by the lightening lead to the formation of organic molecules like amino acids which are the building blocks of life. This was similar to the penetration of earth atmosphere by UV radiation producing the organic compounds from inorganic molecules.
I think C) availability of water is your best answer because alot of organisms count on water as a major resource because they need it to survive so a lack or a gain in the amount of water will majorly effect an ecosystem.
