If-If-Then Calculation (Javascript)

Hello, 

I'm looking to create an if-if-then calculation in my Adobe Acrobat Pro DC. 

There are 3 total fields being utilized, A, B, and C, all with qualitative values (no numbers).

A and B are both drop down menus, each with 3 options. Out of the 9 total combinations between Fields A and B, there will be a return for Field C. The goal is for me to have an Adobe Acrobat where C will dynamically change based on what's in A and B. 

Can anyone assist me in what the javascript code would look like based on what I need done?