which best describes nuclear fusion? a nucleus spontaneously splits and absorbs energy. two nuclei…

which best describes nuclear fusion? a nucleus spontaneously splits and absorbs energy. two nuclei spontaneously combine and absorb energy. a nucleus collides with a neutron and splits, releasing energy. nuclei combine to form a heavier nucleus, releasing energy.
Answer
Brief Explanations:
Nuclear fusion is the process where light - weight nuclei combine to form a heavier nucleus, releasing a large amount of energy. The first option describes nuclear fission. The second option is incorrect as combining nuclei releases energy not absorbs. The third option is also nuclear fission.
Answer:
Nuclei combine to form a heavier nucleus, releasing energy.