Which process generates a greater proportion of energy in stars exceeding about 1.2 solar masses?

Answer

CNO cycle

Stars exceeding $1.2 M_ ext{sun}$ generate a greater proportion of their energy via the CNO cycle, which utilizes carbon, nitrogen, and oxygen as intermediaries to fuse hydrogen into helium.

Which process generates a greater proportion of energy in stars exceeding about 1.2 solar masses?
Coreheatstar