Answer:
Metamorphosis
Step-by-step explanation:
Metamorphosis is the changes in the structure, physiology of an organism. Metamorphosis has seen in the indirect development i.e. egg, larva, and adult. In frog, the egg hatch into fish like larva. They lose gills, and tails as it grows. The lungs and forelimbs appear in the adult frog as it will also exhibit terrestrial life. The metamorphosis initiate by thyroxine hormone secretes from the thyroid gland of the frog.