Please choose the correct answer to the question: Which of the following relationships is true?

Answer1: Play-Doh can scratch diamond, therefore it is softer Answer2: Diamond can scratch Play-Doh, therefore Play-Doh is harder Answer3: Diamond can scratch Play-Doh, therefore diamond is harder Answer4: Play-Doh can scratch diamond, therefore it is harder

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