Which of the following is an example of an organ system?

A.
a human bladder storing waste for removal from the body

B.
a plant's roots absorbing water and minerals from soil

C.
the living material that lines the inside of a cheek

D.
a heart, arteries, and veins all working together

D. a heart, arteries, and veins all working together

D. A heart, arteries, and veins all working together

The correct answer is D. a heart, arteries, and veins all working together.

To identify the example of an organ system among the options given, we need to understand what an organ system is. An organ system is a group of organs that work together to carry out a specific function or set of functions in the body.

To determine which option fits this definition, let's analyze each choice:

A. A human bladder storing waste for removal from the body: While the bladder is indeed an organ, it is not an organ system. It is a component of the urinary system, which includes other organs such as the kidneys, ureters, and urethra.

B. A plant's roots absorbing water and minerals from soil: This is not an example of an organ system. It describes the function of a single organ, the roots, without a coordinated interaction with other organs.

C. The living material that lines the inside of a cheek: This does not represent an organ system either. It refers to the tissue known as the oral mucosa, which lines the inside of the cheek, but it is not an organ system.

D. A heart, arteries, and veins all working together: This option correctly describes an organ system. The heart, arteries, and veins are organs that collaborate to form the circulatory system, which ensures the transportation of oxygen, nutrients, and other essential substances throughout the body.

Therefore, option D, a heart, arteries, and veins all working together, is the example of an organ system among the choices given.