Vertebrates: Fish
Fish is a word used to describe several groups of aquatic vertebrates that breathe through gills and don't have limbs or digits. It basically includes the members of the group Craniata (animals with a skull) except for the Conodonts (extinct organisms without a jaw) and Tetrapods (four-limbed vertebrates).
Fish are very diverse, with approximately 34 300 species described. Of these, around 28 000 species are Osteichthyes or boned fishes, which means most of the fishes have bony skeletons.
So, the sentence should read:
Most fish have bony skeletons.
And the correct answer is E. bony