Bearing in mind that 21 feet is about the distance a normal person can cover in the time it takes a trained shooter to draw and deploy a handgun effectively:
1. B. He's too close for you to draw and shoot; sidestep him and draw after he passes you, then shoot if you need to.
2. D. See above, if you decide to resist the robbery. Since most of us carry our gun close to our wallet, tell him that you'll comply and draw your handgun.
3. C. Give him the car. Surviving is more important than your car.