Why Is Hydrogen Burning the Main Energy Source for Main-Sequence

question 70

Multiple Choice

Why is hydrogen burning the main energy source for main-sequence stars?

• A) Hydrogen is the most common element in stars.
• B) Hydrogen nuclei have the smallest positive charge.
• C) Hydrogen burning is the most efficient of all fusion or fission reactions.
• D) Hydrogen can fuse at temperatures lower than other elements.
• E) All the above are valid reasons.

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