9. Which of the following statements describes the data in Figure 1? a. An increase in sea urchin which of the following statements describe the data in figure 1?

a. an increase in sea urchin biomass is associated with more intense grazing.

b. An increase in sea urchin biomass is associated with greater kelp density.

C. Predation of sea otters by killer whales is associated with greater kelp density.

d. Sea otter abundance was relatively stable from 1972 to 1997.