Please choose the correct answer to the question: A company plants trees on a bare hillside. Which of these is the BEST reason for planting the trees?

Answer1: The trees provide oxygen for the soil. Answer2: The trees prevent soil from washing away. Answer3: The trees make shade for animals living there. Answer4: The trees cause animals to move to other places.

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