Answer the following question given this paragraph: 

Fission is the process in which an atomic nucleus breaks apart into two less massive nuclei. Energy is released in the process in many forms, heat, gamma rays and the kinetic energy of neutrons. If these neutrons collide with nuclei and induce more fission, then a runaway chain reaction can take place. Fission is responsible for nuclear energy and atom-bomb explosions: the fission of uranium acts as a heat source for the Earth’s molten interior.


Q: The process where an atomic nucleus breaks apart into two less massive nuclei is known as ______.

 Choices:

- diffusion

- fusion

- collision

- fission

A:
fission
