You Found a Real Bargain on a Dashboard Fan at a Flea

You found a real bargain on a dashboard fan at a flea market. When you got home, you discovered it was a 6 volt fan that would draw 500 mA at 6 V. Your car has a 12 V system. You need a resistor that will drop 6 V at 500 mA. What value resistor do you need?

A) 18 Ω
B) 12 Ω
C) 6.0 Ω
D) 6.2 Ω