Which of the following is an advantage of using hydrogen as a fuel for vehicles?

• A. Hydrogen fuel cells emit significant amounts of carbon dioxide.
• B. Hydrogen is naturally found in large quantities in Earth's atmosphere.
• C. Hydrogen is denser than gasoline, making storage easier.
• D. Hydrogen combustion produces only water as a byproduct.

Answer: (D)

Verified step by step guidance

1. Understand the properties of hydrogen as a fuel, especially in comparison to conventional fuels like gasoline.
2. Recall that hydrogen combustion or hydrogen fuel cells produce water (H\_2O) as the only byproduct, which means no carbon dioxide (CO\_2) emissions are generated during the energy conversion process.
3. Evaluate the incorrect options: hydrogen fuel cells do not emit significant CO\_2; hydrogen is not naturally abundant in Earth's atmosphere in large quantities; and hydrogen is actually less dense than gasoline, which makes storage more challenging, not easier.
4. Recognize that the key environmental advantage of hydrogen as a fuel is its clean combustion, producing only water, which reduces greenhouse gas emissions and pollution.
5. Conclude that the correct advantage is that hydrogen combustion produces only water as a byproduct, making it an environmentally friendly fuel option.