When analyzing in$-$depth interviews, creating secondary themes, or finding specifics of the main theme is called $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$ For example, the main theme may be satisfaction, but this process will categorize why people were satisfied $($or dissatisfied$)$ such as good$/$bad food, good$/$bad service, etc....

a$.$

Crossroads coding

b$.$

Axial coding

c$.$

Open coding

d$.$

branch coding