The Hormone Insulin Enhances the Transport of Glucose (Sugar) from the Blood

The hormone insulin enhances the transport of glucose (sugar) from the blood into most of the body's cells. Its secretion is controlled by a negative-feedback system between the concentration of glucose in the blood and the insulin-secreting cells. Therefore, which of the following statements is correct?

A) A decrease in blood glucose concentration stimulates insulin secretion, which in turn further lowers the blood glucose concentration.
B) An increase in blood glucose concentration stimulates insulin secretion, which in turn lowers the blood glucose concentration.
C) A decrease in blood glucose concentration stimulates insulin secretion, which in turn increases the blood glucose concentration.
D) An increase in blood glucose concentration stimulates insulin secretion, which further increases the blood glucose concentration.