After Hurricane Katrina, sunflowers and other plants were planted to selectively remove contaminants from the soil. Once the plants matured, they were pulled up by the roots and safely stored with other contaminated wastes. This is an example of After Hurricane Katrina, sunflowers and other plants were planted to selectively remove contaminants from the soil. Once the plants matured, they were pulled up by the roots and safely stored with other contaminated wastes. This is an example of: _________

a. lowering production efficiency.
b. detoxification by phytoremediation.
c. obstruction of nutrient cycling.
d. biological augmentation.
e. reducing primary production.