If you leave your vehicle unattended, you must:

  1. Turn off the engine.
  2. Lock the ignition and remove the key.
  3. Set the parking brake.
  4. All of the above. ✓

Answer: D. All of the above.

You must do all of the above: turn off the engine, lock the ignition and remove the key, and set the parking brake.

Why this is the answer

The handbook says it is illegal to leave a car idling unattended unless you shut off the engine, lock the ignition, take the key out, and set the brake. It also tells drivers that when they leave a vehicle they should turn off the motor, set the parking brake, and remove the key. Each listed action is part of the same unattended-vehicle rule, so the answer that includes all of them is the correct one.

Why the other answers are wrong

Remember it

Remember the sequence as engine off, key out, ignition locked, brake set.

Official handbook: Texas Driver Handbook (DL-7), Chapter 7: Parking, Stopping, or Standing , p. 43

Explanation drafted with AI (deepseek-flash) from the official handbook passage cited above, then checked automatically and by a second model on 2026-10-23. Always confirm with the official handbook.