In the Thermonuclear Process That Is Thought to Heat the Sun

Multiple Choice

In the thermonuclear process that is thought to heat the Sun, the nuclei of which chemical elements are converted to other nuclei to produce the requisite energy?

A) Helium is converted to hydrogen.
B) Iron is transformed to a series of lighter elements in chain reactions, leading eventually to hydrogen.
C) Hydrogen is converted to helium.
D) Uranium is converted to lead.