Gina is scuba diving when she notices a large fish glide over her. it has a flattened body and she notices gills on its underside. which taxonomic group does the fish belong to? a. selachii b. batoidea c. sarcopterygii d. actinopterygii

The correct answer is B. Batoidea

Explanation:

Batoidea is an order of cartilaginous fish which are commonly known as rays. Rays are morphologically different from sharks as their body is flattened and disk-like with very large pectoral fins.  

In rays, mouth and gills are present on the underside of the body. They have five gills that are used for the diffusion of gases and are present on its ventral side but in sharks, gills are present on the side of their head.

Their flattened body helps them to hide in the sand of the ocean floor which prevents them to become prey to large predators like sharks and killer whales. Therefore the right answer is B. Batoidea

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.