The answer is B. phosphodioxide. It is not a pollutant of fossil fuels.
1) reduce the number of trips you take in your car
2) reduce or eliminate fireplace and wood stove use
3) avoid burning leaves, trash, and other materials
4) avoid using gas-powered lawn and garden equipment
5) buying fewer things that are manufactured using fossil fuels
'Climatic variations' and 'Human activities' can be regarded as the two main causes of desertification. removal of the natural vegetation cover(by taking too much fuel wood), agricultural activities in the vulnerable ecosystems of arid and semi-arid areas, which are thus strained beyond their capacity.
It is a beautiful and historic place. has interesting history, shops, and buildings. and the Pope lives very close by.
United States have over 500 million people living