Answer: Option (D) is the correct answer.
Step-by-step explanation:
In fusion reaction, two small nuclei combine together to result in the formation of a large nuclei.
Whereas in fission reaction, large nuclei dissociates into two or more small nuclei.
Nuclear fusion releases more energy as compared to nuclear fission.
For example, two hydrogen nuceli fuse together and result in the formation of helium atom along with release of energy.