Answer: The correct answer is Option c.
Step-by-step explanation:
Hydrogen is the main element that is present in most of the stars. The stars undergo nuclear fusion reaction.
Nuclear fusion reactions are the reactions in which two smaller nuclei combines or fuses together to form a single heavier nuclei.
The reactions which undergo in most of the stars are:

The overall equation for the above reactions is:

The product of the reactions is helium nuclei.
Hence, the correct answer is Option c.