Which Statement About Human Red Blood Cells Is False

Which statement about human red blood cells is false?

A) Hemoglobin production begins once red blood cells mature and enter circulation.
B) Typically, bone marrow produces about 2 million red blood cells every second.
C) The biconcave shape of red blood cells provides a large surface area for gas exchange.
D) The nucleus of a red blood cell is extruded when hemoglobin content reaches about 25 percent.
E) Worn-out red blood cells are removed from circulation in the spleen.