B. The hole in the ozone layer over Antarctica got bigger.
Explanation:
Using the bar scale in the map, we can vividly see that the hole in the ozone layer over Antarctica got bigger. The reduction in the intensity of the blue color in the 2015 suggests that there has been an appreciable decrease in the ozone cover over Antarctica.
Ozone layer is in the stratosphere and it prevents harmful ultraviolet rays from reaching the earth surface.
Over the the years, the increasing use of chlorofluorocarbons in aerosols, as refrigerants have led to a surge in the depletion of this layer.
From the imagery shown on the map, in 2006, we can vividly see a very thick blue cover over Antarctica.
