Ustin weighs 15 pounds less than Greg weighs. Half of Greg's weight is 75 pounds less than Justin's weight. How much does each of them weigh? A. Greg weighs 200 pounds, and Justin weighs 185 pounds. B. Greg weighs 190 pounds, and Justin weighs 175 pounds. C. Greg weighs 180 pounds, and Justin weighs 165 pounds. D. Greg weighs 170 pounds, and Justin weighs 155 pounds.