Correct Answer: Spleen

Solution : The correct answer is Spleen.

The spleen is known as the graveyard of RBCs. They have a life span of 120 days and after they die, they are ingested by free macrophages in the spleen. It helps in purifying blood, removes old and damaged cells and controls their levels. It also contains White Blood Corpuscles (WBC) and fights antigens that enter the bloodstream. It is one of the largest lymphatic organs in the human body.