Final answer:
The correct answer to the question regarding vertebrates in the group chordates is Option A: Fish, Amphibians, Reptiles, Birds, and Mammals, as these are all vertebrates that belong to the phylum Chordata and share the presence of a notochord during their embryonic development.
Step-by-step explanation:
Five vertebrates that are in the group chordates are: Fish, Amphibians, Reptiles, Birds, and Mammals. These categories represent the diversity of the vertebrates which are part of the phylum Chordata. They all share a common feature in their developmental stages, which is the notochord - a flexible rod-shaped body found in the embryonic stage of all chordates. The vertebrate subgroup includes organisms with a backbone and is the most conspicuous and familiar group within the Chordata.
As for the options provided:
- Option A) Fish, amphibians, reptiles, birds, mammals - is correct.
- Option B) includes insects and arachnids, which are not chordates but arthropods.
- Option C) includes crustaceans, another group of arthropods.
- Option D) includes mollusks, which belong to a different phylum entirely.