What process is the main engine for hydrogen fusion in stars significantly more massive than the Sun?

Answer

Carbon-Nitrogen-Oxygen (CNO) cycle

In stars significantly more massive than the Sun, which are hotter, the CNO cycle takes over as the primary engine, utilizing carbon, nitrogen, and oxygen isotopes as catalysts to convert hydrogen into helium.

What process is the main engine for hydrogen fusion in stars significantly more massive than the Sun?
ElementstellarstarFusionnucleosynthesis