Which Hormone,made by the Kidney,is Necessary for Red Blood Cell

Question

Which hormone,made by the kidney,is necessary for red blood cell production by bone marrow?  
A) Erythropoietin
B) Hemoglobin
C) Insulin
D) Erythrocytes
E) Leucocytes

Accepted Answer

Erythropoietin is a hormone produced by the kidneys that stimulates the production of red blood cells in the bone marrow.