Which one among the following animals can perform respiration either through gills or through lungs?

The correct answer is Frog. Frogs are amphibians that exhibit different respiratory methods depending on their life stage and environment. In their larval stage, known as tadpoles, they live underwater and breathe through gills. As they undergo metamorphosis into adults, they develop lungs for breathing air on land. Additionally, adult frogs can respire through their moist skin (cutaneous respiration), which is particularly useful when they are submerged in water. While specific species like lungfish can breathe using both organs, "Fish" as a general category is primarily associated with gills. Snakes (reptiles) and cows (mammals) are terrestrial animals that rely exclusively on lungs for respiration.