<span>300BC was the approximate year.
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The correct answer is transitional.
Gerobatrachus refers to an extinct genus of amphibamid temnospondyl, which thrived in the initial Permian, that is, about 290 mya, in the region, which is now known as Baylor County, Texas. The transitional form of fossils are those that demonstrate the intermediate form between the two distinct living species, it could be in a form of an ancestor and its descendants. It is considered that the frogs and salamanders have evolved from a common ancestor of primitive amphibian tetrapod subclass known as Temnospondyli.
D. Proteins are composed of amino acids and determines all the structures and functions of the organism.
