Final answer:
The statement is an inference, not an observation, as it is a conclusion about the amphibian lifestyle of a frog based on its ability to live in both land and water. Amphibians have adapted features for life in both environments, and there are distinct traits between frogs and toads based on their respective habitats.
Step-by-step explanation:
The statement that a frog is an amphibian because they can live both on land and in water is an inference. An observation would be something that can be directly seen or measured, such as noting the frog's moist skin or its jumping behavior. An inference, on the other hand, is a conclusion drawn from observations, and stating that a frog is an amphibian due to its ability to live in both environments is a conclusion drawn from understanding its lifestyle and characteristics.
Amphibians, including frogs and toads, exhibit adaptations for both aquatic and terrestrial life. As larvae, they live in water and have gills for breathing; as adults, they primarily live on land and have lungs—as well as the ability to breathe through their skin—for respiration. Frogs and toads differ in physical attributes and habitats, with frogs having moist, smooth skin and longer legs for jumping, often living closer to water, while toads have drier, bumpier skin, shorter legs, and spend more time on land.