Which element is the primary constituent of most stars?

• A. Oxygen
• B. Carbon
• C. Hydrogen
• D. Helium

Answer: (C)

Verified step by step guidance

1. Understand that stars are primarily composed of elements that are abundant in the universe and formed during the early stages of cosmic evolution.
2. Recall that hydrogen is the simplest and most abundant element in the universe, making it the main fuel for stars through nuclear fusion.
3. Recognize that in stars, hydrogen nuclei fuse to form helium, releasing energy that powers the star.
4. Note that while elements like oxygen and carbon are present in stars, they are much less abundant compared to hydrogen and helium.
5. Conclude that hydrogen is the primary constituent of most stars due to its abundance and role in stellar fusion processes.