Question: Blood glucose level is regulated by two antagonistic hormones, glucagon and insulin. The following graph shows the fluctuations in an individual's blood glucose level over a five hour period: . From the information provided above and your knowledge of physiology, which of the following statements are appropriate? I. Normal homeostatic mechanisms maintain a glucose concentration of approximately 1 mg/ml. II. Glucagon is released at points A and C. III. The individual eats a meal at point D. IV. Insulin is being released at points B and E. A) I only  B) I and II only  C) I and IV only  D) I, II, and III only. Please choose an answer from [A, B, C, D].
Answer: C