Assume the cost of aluminum used by​ soft-drink companies increases. Which of the following correctly describes the resulting effects in the market for canned soft​ drinks? I. The demand for soft drinks decreases. II. The quantity of soft drinks demanded decreases. III. The supply of soft drinks decreases. IV. The quantity of soft drinks supplied decreases. A. I and IV. B. IV only C. III only. D. II and III.