We have already lost some 80 percent of the coral reefs in the Caribbean over the last three decades, and losses in the Pacific Ocean are also widespread. Reefs are like cities, with some parts growing and some parts being destroyed. When the net growth is positive, reefs can persist. Amazingly, coral reefs are threatened by such atmospheric conditions as

A) the growing hole in the ozone.
B) carbon dioxide emissions and global warming.
C) increases in UV radiation and the amount of reflected light.
D) increased particulate matter resulting in decreased UV rays.