Which one of the following has the highest fuel value?

The fuel value of a substance, also known as its calorific value, refers to the amount of heat energy produced during the complete combustion of a unit mass of that fuel. Hydrogen has the highest fuel value among all known fuels. It releases approximately 150 kilojoules of energy per gram. In comparison, gasoline, natural gas (methane), and charcoal produce significantly less energy per unit mass. For example, natural gas produces about 50 to 55 kilojoules per gram, while gasoline produces about 45 to 48 kilojoules per gram. Because of its exceptionally high energy density and the fact that it burns cleanly to produce only water vapor, hydrogen is used as a primary fuel in high-performance applications like space rocket propulsion.