Majority of animals on earth are classified as invertebrates. They are the cold-blooded animal that do not have a backbone. They can be found on land or water. 98% are invertebrates while 2% are vertebrates.
Mammals are vertebrates and humans are the most common mammals on Earth. Radial symmetric does not possess left and right sides. An example is a jellyfish.
Answer - Option 4 - Invertebrate