Answer:
D. The cells in group B are prokaryotic because they replicate their DNA in the cytoplasm.
Explanation:
The cells of group A are prokaryotic because it is prokaryotes which do not have a double membranous structure called nucleus for storing their genetic material. The genetic material of prokaryotes is spread in the cytoplasm in the form of a circular DNA which is called as nucleoid. Since they do not have a separate organelle like nucleus for storage of their genetic material, they are bound to replicate their DNA in the cytoplasm. In contrast to prokaryotes, eukaryotes have nucleus for storage of their genetic material and in eukaryotes replication is an exclusively nuclear event.
Like all other reptiles, birds have scales. Also, birds lay eggs like other reptiles.
The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary (K–T) extinction) was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago.