Please choose the correct answer to the question: The orbit of Earth is almost circular and has a period of about 365 days. Compared to the orbit of Earth, which of these objects usually have highly elliptical orbits and can have periods of over 1000 years?

Answer1: asteroids Answer2: meteorites Answer3: comets Answer4: moons

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