Answer: Option (b) is the correct answer.
Explanation:
A nuclear fusion is defined as the reaction in which two small nuclei combine together and result in the formation of a large nuclei.
For example, [tex]^{2}_{1}H + ^{2}_{1}H \rightarrow ^{4}_{2}He[/tex]
On the other hand, a reaction in which a large nuclei divides into two small nuclei is known as a nuclear fission reaction.
For example, [tex]^{238}_{92}U \rightarrow ^{234}_{90}Th + ^{4}_{2}He[/tex]
Thus, we can conclude that colliding hydrogen atoms to produce heavier helium atoms would be an example of nuclear fusion.
