Checkbox Yes/No field returns value in other field

Hello, i hope someone can help me on this. I have 3 columns and below is an example of my list

question A : checkbox yes/no

question B: checkbox yes/no

and i have status column with 3 choices

if question  A and question  B is not checked it will return in status field  "not completed"

If question A is only checked it will return in status field  "1st completed"

if question  A and question B has been checked both it will return in status field "completed"

please if my question is not clear i will give you more details

Thanks in advance