Which of the following is discussed in paragraph 5 as a disadvantage of slope soaring as compared to thermal soaring A. Slope soaring does not allow a bird to remain at a constant altitude. B. Gliders tend to travel at slower speeds during slope soaring than during thermal soaring. C. Slope soaring is limited to the area where the particular slope is located. D. It is difficult to predict the location of an area suitable for slope soaring.