Which among these is the correct combination of aquatic mammals?

The class Mammalia is characterized by the presence of hair, diaphragm, mammary glands and three specialized bones in the middle ear. Whales, dolphins and seals are aquatic in their habitat. However, they show the presence of mammary glands to nourish their young ones. They are warm-blooded and breathe with the help of their lungs. Thus, the correct answer is option A (Whales, Dolphins, Seals).