Here's why:
* Mammals are warm-blooded animals that have fur or hair, give birth to live young, and nurse their offspring with milk.
* Amphibians are cold-blooded animals that live in water and on land. They have smooth, moist skin and lay eggs in water.
* Reptiles are cold-blooded animals that have scales or scutes, lay eggs, and breathe air.
Angelfish have gills, fins, and scales, all features characteristic of fish.