Many Physiological Conditions Are Related to Particular Proteins in Cell

Many physiological conditions are related to particular proteins in cell membranes. The number of insulin receptors in membranes is related to the amount of insulin present around those cells. If the presence of increased insulin results in a decrease in receptors and a decrease in insulin results in an increase in insulin receptors, this would be an example of

A) a metabolic pathway.
B) negative or regulatory feedback.
C) passive transport.
D) competitive inhibition.