Final answer:
The spleen does not recycle aged erythrocytes.
Step-by-step explanation:
The spleen serves as a blood reservoir, filters blood, filters lymph, and houses lymphocytes. However, it does not recycle aged erythrocytes. The red pulp of the spleen removes damaged red blood cells and replaces them with new ones, while the white pulp is rich in lymphocytes that remove antigen-coated bacteria from the blood. Therefore, option D, recycling aged erythrocytes, is not a function of the spleen.