The correct answer is: A. 100 days.
Red blood cells (RBCs) are the most common type of blood cell and are responsible for carrying oxygen from the lungs to the rest of the body. They are produced in the bone marrow and have an average lifespan of 100 days. After this time, they are destroyed by the spleen and other organs.
The lifespan of RBCs is determined by a number of factors, including their age, shape, and size. Older RBCs are more likely to be destroyed, as are those that are misshapen or too large. The lifespan of RBCs can also be affected by certain diseases, such as sickle cell anemia and thalassemia.
RBCs are essential for life and their destruction can lead to a number of health problems, including anemia. Anemia is a condition in which the body does not have enough healthy red blood cells. This can cause symptoms such as fatigue, shortness of breath, and pale skin.
There are a number of treatments for anemia, including blood transfusions, iron supplements, and medication. In some cases, a bone marrow transplant may be necessary.
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