The pictures below show one of Earth's polar ice caps in 1984 and 2012.
What change is shown in these pictures?
A.
a decrease in Earth's carbon dioxide levels due to it being absorbed into and breaking the ice cap
B.
an increase in temperature of Earth's internal core rising to Earth's pole and melting the cap
C.
a continent drift due to part of the polar ice cap receding and moving to a new location
D.
a decrease in the size of the ice cap due to Earth's changing and evolving climate