Answer:
A. Uniformitarianism
Explanation:
The principle of Uniformitarianism was proposed by a Scottish Geologist, James Hutton.
The principle is simply stated as "the present is the key to the past".
The processes that have occurred in geologic past is still in play today. By looking at rock sequences in our present day, we can actually have a firm grasp of the processes they have undergone in the past.
The answer is: subduction zones.
Different types of blood contact different kinds of antigens and antibodies. For example, Type A blood has A antigens and B antibodies, antibodies being the thing that fights B antigens. Type B blood has B antigens and A antibodies. So if someone with type B gets transfused with Type A blood, the person's antibodies will attack the new blood.
