Question

the circulatory system of a whale is considered an organ system because it is composed of different
a cells.
b tissues.
c organs.
d molecules.
e hearts.

Explanation:

An organ system is made up of different organs that work together to perform a specific function. The circulatory system of a whale, like in other organisms, consists of organs such as the heart, blood - vessels, etc. Cells make up tissues, tissues make up organs, and organs make up organ systems. Molecules are at a lower biological level and a heart is just one part of the circulatory system.

Answer:

C. organs