Answer: Fission
Fission is the splitting of nuclei.
Explanation:
Keep in mind that a nuclear fission is a nuclear reaction where the nucleus of an atom will be divided into 2 smaller, lighter nuclei.
also the Fission is a way of the nuclear transmutation because the fragments that we are getting, are not the same product as the first or the original atom. The two nuclei that we get are similar but with a slowly different sizes.
the energy that we produce during this process is bigger than we get with all the gasoline of the world, because of the forces through a nuclei is united.