Correct Option: C

The source of the sun’s fuel is hydrogen and helium gases. Through a special chemical reaction, called nuclear fusion, the hydrogen gas is “burned” releasing an enormous amount of energy in the form of light and heat. In nuclear physics, nuclear fusion is a nuclear reaction in which two or more atomic nuclei join together, or “fuse”, to form a single heavier nucleus. During this process, matter is not conserved because some of the mass of the fusing nuclei is converted to energy which is released. Fusion is the process that powers active stars. The fusion of two nuclei with lower masses than iron (which, along with nickel, has the largest binding energy per nucleon) generally releases energy, while the fusion of nuclei heavier than iron absorbs energy. The opposite is true for the reverse process, nuclear fission.