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
Due to the linneaus system of classification scientist were able to identify organism name , group via standardized system . They have found similarities in the organism like DNA / RNA ( genetic composition), embryonic development etc . so that they can study a organism completely . With the help of this system of classification scientist were able to give a particular name to a organism which is standardrized in the whole universe. It makes easier to all to identify an organism , otherwise different places have different name for a particular species.