How do you secure a parked automatic-transmission vehicle (except for a vehicle with a robotic gearbox)?

1. Shift into reverse gear (R) and secure the parking brake.
2. Correct answer: Shift into parking gear (P) and secure the parking brake.
3. Shift into neutral gear (N) and secure the parking brake.
4. Shift into first gear (1) and secure the parking brake.

WhyAn automatic car is secured by putting it in P and applying the parking brake.