According to this information, which of the following is an example of an ecological disaster?

Exhibit:

According to this information, which of the following is an example of an ecological disaster?
A . millions of fish swimming to one particular area
B . bears waking from winter hibernation and leaving national parklands
C . an oil tanker spilling its cargo into the sea
D . worldwide demands for fuel
E . the fishing industry catching many salmon

Answer: C