Food intake of grazing animals is limited by the rate grass can be chewed and swallowed, as well as the rate at which food can be digested. The authors of the paper “What Constrains Daily Intake in Thomson’s Gazelles?” (Ecology [1999]: 2338–2347) observed the grazing activity of captive Thomson’s gazelles. They recorded grazing rate (amount of grass eaten, in grams per minute) and biomass of the grazing area (food density, in grams per square meter). Scatterplots of these data with four possible functions that might be used to describe the relationship between grazing rate and biomass are shown in the figure at the bottom of the page. Which of these functions would you recommend? Explain your reasoning in a few sentences.