What does the CNO cycle and the hydrogen proton-proton cycle have in common? Choose the best answer to the question.
A) They both are ways to fuse hydrogen nuclei to make helium.
B) They are both nuclear reactions; the CNO cycle makes carbon, nitrogen, and oxygen, and the proton cycle makes helium.
C) They are both cycles in star lives.
D) They both trigger at the same temperature.

Question

Quizplus · Accepted Answer

Both the CNO cycle and the proton-proton cycle are ways to fuse hydrogen nuclei to make helium. The proton-proton cycle is the dominant process in low-mass stars, while the CNO cycle is the dominant process in high-mass stars.

What Does the CNO Cycle and the Hydrogen Proton-Proton Cycle