Which of the following represents the correct combination of a taxonomic group with its characteristics, without any exception?

All amphibians are cold blooded animals. In all amphibians, eyelids, cloaca and 3 chambered heart are present. Among reptiles, turtles, sea snakes, freshwater snakes, crocodiles are aquatic animals. Among Aves, some are flightless birds (e.g. Ostrich). Among mammals, some are aquatic or flying.