World War I & World War II
Are there any options for that question?
Answer:
Are more severe :) Hope this helps
Answer:
The heart is a muscular organ in most animals, which pumps blood through the blood vessels of the circulatory system. Blood provides the body with oxygen and nutrients, as well as assisting in the removal of metabolic wastes. In humans, the heart is located between the lungs, in the middle compartment of the chest.