Microsoft Word If Statements - How to reference a text field?

I'm trying to make a simple dynamic form in Microsoft Word. I have a text line that says "Project Type: ". The Project Type is either going to be "A", "B", or "C". If "Project Type:" = "C" then I need to have the short version of the document, and if "Project Type" = "A" or "B" then I need to have the full version of the document.

I can insert an "If statement" through merged mail but I don't know how to reference my text (if text = A, B, or C). How can I do this in word to create a dynamic form?

Again, If a user types in "A" they get a long form, if they type in "C" they get a short form.

Thank you!

Jonathan