The correct option is D Location is not polluted
Lichens are composed of algae and fungi living together in a symbiotic relationship. Sulfur dioxide, is a pollutant which when mixed with rainwater or air can damage lichens and does not allow them to grow due to which they act as natural indicators of air pollution. Therefore the absence of lichens indicates that the area is heavily polluted with sulfur dioxide. Thus, the correct answer is option D.