Which of the following can reduce biodiversity within a natural environment?
a. giant kangaroo rats enrich the soil for plants with their piles of grass clippings in the california grasslands.
b. grasslands in the california floristic province have been converted into housing projects, shopping centers, and roads.
c. acacia trees of central and south america provide food for stinging ants, while the stinging ants sting other insects on the trees.
d. in japan, hummingbird hawk moths drink nectar from a species of flowering plants and transfer the plants' pollen to other flowering plants of the same species.