Question

multiple choice question
what vertebrate group is characterized by four - chambered hearts, feathers, and endothermy?
birds
mammals
nonavian reptiles
reptiles

Explanation:

Birds are vertebrates with four - chambered hearts (which helps in efficient oxygen transport), feathers (for flight, insulation etc.), and are endothermic (can regulate their body temperature internally). Mammals have four - chambered hearts and are endothermic but lack feathers. Non - avian reptiles and reptiles (assuming non - avian reptiles is a subset of reptiles in this context) are ectothermic (depend on external heat sources) and lack feathers.

Answer:

birds