The answer is A.
Why: The heart is part of an organism, so that doesn't exactly count. Soil is not alive, and neither is clay. Therefore, Bacteria must be it. Bacteria is a living thing, and can function by itself.
The correct answer is that bones do not have a role in glycogen production. Glycogen is only produced by two organs of the body; the muscles and the liver. Bones and bone structures function to support movement by serving as insertions for the muscles. The tissue inside the bone is called the bone marrow; which is divided into red marrow (functions for blood cell formation) and yellow marrow (functions to store fat).
A dog breathes in oxygen and then releases carbon dioxide when he exhales. Conversely, a tree gives off oxygen and takes in carbon dioxide. So the breath of the dog sustains the tree while the output of oxygen for the tree sustains the dog.
