In an experiment, enzymes X and Y were tested. Enzyme X came from bacteria living in rivers and lakes at temperatures from $5\,^{\circ}\text{C}$ to $20\,^{\circ}\text{C}$. Enzyme Y came from bacteria living in hot water springs at temperatures from $40\,^{\circ}\text{C}$ to $85\,^{\circ}\text{C}$. The experiment recorded the concentration of product made by each enzyme at temperatures between $0\,^{\circ}\text{C}$ and $100\,^{\circ}\text{C}$ after 5 minutes. Which graph shows the results?
Biology 9700 · AS & A Level · Factors that affect enzyme action