Final answer:
The set of animals made up exclusively of amphibians is Salamandra, Ichthyophis, Hyla. Hence option 3 is correct.
Step-by-step explanation:
Amphibians are a class of cold-blooded vertebrates known for their life cycle that typically involves both aquatic and terrestrial phases. Let's analyze each set to understand why Option 3 is correct:
Salamandra: Salamanders are amphibians that belong to the order Urodela. They have a lizard-like appearance and typically have a larval aquatic stage and an adult terrestrial stage.
Ichthyophis: Ichthyophis refers to a genus of amphibians commonly known as caecilians. Caecilians are limbless and often resemble large worms. They are amphibians despite their snake-like appearance.
Hyla: This refers to the genus of tree frogs. Tree frogs are a type of anuran amphibian, and they undergo metamorphosis from aquatic tadpoles to terrestrial adults.
Option 1 includes "Labeo," which is a genus of fish, and Option 2 includes "Exocoetus," which is a genus of flying fish. These options include non-amphibian species. Option 4 includes "Chelone" and "Clarias," which are a genus of turtle and a genus of catfish, respectively, both of which are not amphibians. Therefore, Option 3 is the correct set consisting exclusively of amphibians.