The correct answer is A. Remain in the car.
If you are caught in a thunderstorm while driving, the safest place to be is in your car. The metal frame of the car will act as a Faraday cage, protecting you from the lightning strike. If you can, pull over to the side of the road and stop. If you cannot pull over, stay in the car and keep your hands off of the steering wheel and any metal objects.
Option B is incorrect because getting out of the car will put you at risk of being struck by lightning. Lightning is attracted to tall objects, and you will be the tallest object if you are standing outside of the car.
Option C is incorrect because taking shelter under a nearby tree will also put you at risk of being struck by lightning. Trees are tall objects that are easily attracted to lightning.
Option D is incorrect because touching an electric pole will also put you at risk of being struck by lightning. Electric poles are made of metal, which is a conductor of electricity. If you touch an electric pole during a thunderstorm, you will be a path for the lightning to travel to the ground.