Nancy Lerner is taking a course from Professor Good heart who will count only her best midterm grade and from Professor Stern who will count only her worst midterm grade. In one of her classes, Nancy has scores of 50 on her first midterm and 45 on her second midterm. When the first midterm score is measured on the horizontal axis and her second midterm score on the vertical, her indifference curve has a slope of zero. This class could:.
a. be Professor Good heart's but could not be Professor Stern's. b. be Professor Stern's but could not be Professor Good heart's. c. not be either Professor Good heart's or Professor Stern's. d. be either Professor Good heart's or Professor Stern's. e. none of the above.