Final answer:
The scales that closely resemble teeth in both structure and origin can be found in chondrichthyans, which are cartilaginous fishes like sharks and rays.
Step-by-step explanation:
The scales that closely resemble teeth in both structure and origin can be found in c. chondrichthyans, which refers to cartilaginous fishes like sharks and rays. These fishes have tooth-like scales called dermal denticles that are made of enamel and dentin, just like the teeth of other vertebrates.
The dermal denticles provide protection and reduce drag in the water. The scales that closely resemble teeth in both structure and origin can be found in chondrichthyans, which are cartilaginous fishes like sharks and rays.