Correct Option
The correct option isEgg -> Tadpole -> Adult
Explanation
Frogs are amphibians that undergo metamorphosis, a biological process involving a distinct and abrupt change in body structure during development from the larval stage to the adult stage.
Detailed Analysis
The life cycle of a frog follows a specific chronological order:
- Egg: The cycle begins when an adult female frog lays clusters of eggs, known as spawn, in a water body. These eggs are fertilized externally.
- Tadpole (Larva): The eggs hatch into tadpoles. Tadpoles are fully aquatic, possess gills for respiration, and have a tail for swimming. Morphologically, they are distinct from the adult form.
- Adult: Through metamorphosis, the tadpole undergoes significant physiological changes: legs develop, the tail is reabsorbed, and lungs develop to replace gills. The organism transforms into an adult frog capable of living on land and reproducing.
Therefore, the scientifically correct sequence is Egg → Tadpole → Adult.
Key Takeaway: Amphibians exhibit indirect development, where the organism passes through a larval stage (tadpole) that is structurally different from the adult, requiring metamorphosis to reach maturity.