Please choose the correct answer to the question: A car runs out of fuel while traveling on a level road and eventually comes to a stop. Which of the following best explains why the car stops?

Answer1: Some of the energy of the car was lost to friction. Answer2: Some of the energy of the car was destroyed. Answer3: The amount of kinetic energy increased. Answer4: The amount of useful energy increased.

Answer format: answer1/answer2/answer3/answer4
Answer: answer1