The graph on the left shows the total supply and consumption of forests when the consumption rate and population growth rate are both low. The graph on the right shows land usage under the same conditions.
What happens to grasslands and wetlands as forests are used up?

A. The percentage of land used as either grassland or wetland increases.
B. The percentage of grassland increases, while the percentage of wetland decreases.
C. The percentage of land used as either grassland or wetland decreases.
D. The percentage of grassland decreases, while the percentage of wetland increases.