ANSWER
Small nuclei combine, then form larger nuclei.
Option C
EXPLANATION
Nuclear fusion is defined as the process in which two or more light stable nuclei combined together to form a larger nuclei
In the star region, elements are squeeze together to produce a larger one in a process called fusion. Star fuse hydrogen atoms into helium. Helium atoms then fuse to create beryllium and the process continues like that until iron is formed.
Therefore, the correct answer is option C
