The skulls and pelvis of some dinosaurs have the same characteristics as the skulls and pelvis of all modern birds, but not all dinosaurs have such characteristics. Some scientists claim that all animals with such characteristics are dinosaurs. Based on the above statement and the claims of scientists, can it be launched? ['Birds have more similarities to dinosaurs than other animals.', 'Some ancient dinosaurs are no different from modern birds.', 'All dinosaurs are birds.', 'Modern birds are dinosaurs.']