Proton-proton chain reaction is: the destruction of energy due to lost atoms. the creation of energy through the process of nuclear fusion. the sharing of energy through radioactive zone. the decline of energy due to a solar eclipse.

The creation of energy through the process of nuclear fusion.

Explanation:

A hydrogen atom is called a proton since it has one proton and zero neutrons, in its nucleus. Nuclear fusion is a process in which lighter nuclei  will combine to form a heavier nucleus . Proton - proton chain reaction occurs in stars. Sun is one of the stars in which the energy release is due to the proton - proton chain reaction.  It generates nuclear energy . The combination of one hydrogen with another results in the formation of helium atom and the fusion energy after a series of reactions.