Answer: The correct answer would be the fourth option.
Explanation:
Water is a chemical compound formed from oxygen and hydrogen. Its chemical formula is H₂O. It is polar inorganic compound. It is essential for life as life would not be possible without water. It helps in stabilizing the global temperature as well as body temperature of living organisms.
However, it is not the most abundant molecule in the atmosphere. The nitrogen is the most abundant gas present in the atmosphere which nearly makes 78 percent of the atmosphere. The water vapours hardly makes 1 percent of the atmosphere.