Please choose the correct answer to the question: Noah studied different systems in the human body. Which best describes a function of veins in the circulatory system?

Answer1: carrying blood from the body to the heart Answer2: supplying nutrients from the intestines to the body Answer3: carrying carbon dioxide from the body to the lungs Answer4: passing waste materials from the blood to outside the body

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