I am taking a large leap here but I could see:
What do you think MD will give you that DNP does not?
Why now?
How do you think you've prepared for the change from DNP to MD?
No doubt you've already thought about those. I've heard from a friend of mine - older nontrad like me - who said her interviews were more like open ended discussions. I believe she got in everywhere she applied by ... being herself 🙂
Go be you!