The study of animals' structures, behaviors, functions, and evolution is called ethology zoology biology physiology

The correct answer is zoology.

Explanation:

zoology is the branch of biology in which one study the behaviors, structures, evolution and functions of the animals. It is also known as animal science. In Animal science, you study all the aspects of animals from its evolution to the structures to the structural and functional unit of the cell.

This discipline can include animal anatomy, biochemistry, physiology, genetics, evolution, ecology, behavior, evolution, and conservation.

Thus, the correct answer is zoology.