Catherine is working on a study of different groups of animals. In which group of animals would she find the most diversity?

The correct choice would be Mammals.

Answer: Invertebrates

Explanation:

The invertebrates have the most diverse group of animals. They neither posses nor develop vertebral column.

They include different types of animals excluding a small sub phylum vertebrae.

Of all the total animals on earth 97 % of the animal species are invertebrates. This consists of all the organism that includes marine organisms and terrestrials organisms as well.