Final answer:
option b,Hydrogen is the most abundant element in the universe, essential for forming compounds like water and organic molecules. Rarely found in elemental form on Earth, it forms bonds with elements such as carbon and oxygen.
Step-by-step explanation:
Hydrogen, the most abundant element in the universe and a major component of numerous compounds, plays a crucial role in various chemical processes. Present in water (H2O) and hydrocarbons, hydrogen's ability to form bonds with elements like carbon and oxygen is fundamental to organic chemistry.
On Earth, hydrogen's reactivity means it's rarely found in its elemental form; instead, it is usually part of compounds such as water or organic molecules like petroleum. Water, which covers about 70% of the Earth, is the most common hydrogen compound and is essential to all known forms of life. Combustion of hydrocarbons, such as those found in gasoline, involves hydrogen reacting with oxygen to produce water and energy. The name 'hydrogen' itself implies its role as the 'water maker'.