PLEASE HELP!! IM TIMED!! WILL MARK BRAINLIEST!! 13 POINTS!! SCIENCE!!

What best explains the source of light energy and heat energy produced by a star?

A. Dense metals, such as iron, explode in the core of a star.
B. Explosions from a nearby supernova provide fuel to the star.
C. Nuclear reactions involving the fusion of atoms occur in the core of a star.
D. High-energy radiation from nearby stars penetrate the core of a star.