Suppose the tissue cells by letter D are undergoing an unusually high amount of metabolic activity and as a result producing more H⁺ than usual. What can you conclude about the CO₂ levels near letter F? A. CO₂ would be at 40mm Hg B. CO₂ would be at 46mm Hg C. CO₂ would be below 40mm Hg D. CO₂ would be higher than 46mm Hg