The correct option is D Homeothermy
Homeothermy - is thermoregulation that maintains a stable internal body temperature regardless of external influence.
Birds and mammals are homeotherms.
Kangroos are marsupials, a sub-type of mammal, females have pouches that contain mammary glands, where their young live until they are old enough to emerge.
Platypuses are monotremes i.e., they are egg laying mammals.
So parrot, platypus and kangroo are all homeotherms.