As a Main-Sequence Star Burns Its Core Supply of Hydrogen

question 14

Multiple Choice

As a main-sequence star burns its core supply of hydrogen, what happens?

• A) Helium begins to fuse throughout the core.
• B) Helium fuses in a shell surrounding the core.
• C) Helium fusion takes place only at the very center of the core, where temperature and pressure are highest.
• D) Helium builds up as ash in the core.
• E) Helium builds up everywhere in the star's interior.

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