(Figure: Kelsey's annual demand) The graph shows Kelsey's annual demand for rental cabins at a state park on the lake. A graph has number of stays per year along the horizontal axis ranging from 0 to 4, in increments of 1, and rate of nightly rentals along the vertical axis ranging from 0 to 160 dollars, in increments of 40 dollars.The Demand line passes through the following points: (0, 160), (1, 120), (2, 80), (3, 40), and (4, 0). All values are approximate. What is true if the nightly rental rises from $80 to $120? a. Kelsey's marginal benefit from stays at the park would fall by up to $119.99. b. Kelsey's marginal benefit from stays at the park would fall by up to $79.99 c. Kelsey's marginal benefit from stays at the park would fall by $80.00 d. Kelsey's marginal benefit from stays at the park would fall by less than $80.00