The correct answer is option 3: Myxine. Myxine, also known as hagfish, is a type of jawless fish. Jawless fish are a class of vertebrates that lack jaws, which are considered an important feature of most other fish species. Instead of jaws, hagfish have a circular mouth with sharp teeth-like structures that they use to scrape food. They are often found in cold ocean waters and are known for their slimy appearance and ability to produce copious amounts of slime for defense. Sphyma (option 1) and Trygon (option 2) are sharks, which have jaws. Therefore, they are not jawless animals. The mention of Shark (option 4) is unnecessary as the question specifically asks for a jawless animal.