which process occurs in a controlled fusion reaction?

Question

1 light nuclei collide to produce heavier nuclei.
2 heavy nuclei collide to produce lighter nuclei.
3 neutron bombardment splits light nuclei
4 neutron bombardment splits heavy nuclei. is it 1 ?

Answer 1

I am sure that I have answered this one recently.

Fusion is the process where light nuclei, such as hydrogen, fuse to form heavier nuclei. So yes 1.