Answer:
provide the rationale before making the request.
Explanation:
Your rationale is basically the supporting logic and reasons why you are proposing that specific solution or decision.
In this case, if you believe that your audience might resist your proposed solution, then before you propose it, you must give the reasons why you are doing so. I.e. you must tell them the rationale behind your decision to propose that solution in an attempt for them to better understand it.