Formatting a forced choice following a DCE choice set with an opt-out option

Hello,

In my survey, I have included a third alternative in the DCE which acts as an opt-out. Should participants choose this alternative/the opt-out, I would like to follow up with a question on the same choice task which forces participants to make a choice i.e. “What would you pick if you had to select between A or B?”

I was wondering if I can program this forced choice task in the software ,and, if so, how.

Thank you,
Sinead