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

which best describes nuclear fission? 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
Answer:
C. A nucleus collides with a neutron and splits, releasing energy.
Brief Explanations:
Nuclear fission is when a heavy - nucleus (e.g., uranium - 235) absorbs a neutron and then splits into two or more smaller nuclei, releasing a large amount of energy. Option A is incorrect as fission is not spontaneous and releases energy, not absorbs. Option B describes fusion (nuclei combining) and is incorrect for fission. Option D also describes nuclear fusion.