Which statement best describes the relationship between birds and dinosaurs as presented?

Which statement best describes the relationship between birds and dinosaurs as presented?

• A. Birds are living dinosaurs descended from feathered theropods.
• B. Birds are unrelated to dinosaurs
• C. Birds evolved after dinosaurs disappeared
• D. Birds are mammalian descendants

Answer: (A)

Birds are living dinosaurs descended from feathered theropods. This is supported by fossil evidence showing feathers and many anatomical similarities between birds and theropod dinosaurs, including transitional fossils like Archaeopteryx that illustrate how flight-related features developed within that lineage. When the mass extinction at the end of the Cretaceous erased most non-avian dinosaurs, birds—the surviving branch of the theropod group—continued and diversified into the variety of species we see today. So the best description is that birds are living dinosaurs descended from feathered theropods. The other statements don’t fit because birds are not unrelated to dinosaurs, they did not evolve after dinosaurs disappeared, and they are not mammals.

Birds are living dinosaurs descended from feathered theropods. This is supported by fossil evidence showing feathers and many anatomical similarities between birds and theropod dinosaurs, including transitional fossils like Archaeopteryx that illustrate how flight-related features developed within that lineage. When the mass extinction at the end of the Cretaceous erased most non-avian dinosaurs, birds—the surviving branch of the theropod group—continued and diversified into the variety of species we see today. So the best description is that birds are living dinosaurs descended from feathered theropods. The other statements don’t fit because birds are not unrelated to dinosaurs, they did not evolve after dinosaurs disappeared, and they are not mammals.