Q: What are endothermic vertebrates with legs?\nOptions:\n- (A) Birds\n- (B) mammals\n- (C) Snakes\n- (D) ducks\n- (E) Lizards\n- (F) ants\n- (G) long\n- (H) toads
Let's think step by step below.

User
Birds are endothermic tetrapod vertebrates. Legs define Tetrapods. Birds are endothermic vertebrates with legs.
Thus, the answer is (A).
Assistant