Which statement best evaluates the dual roles of bicarbonate in erythrocytes?

• A. Bicarbonate only facilitates CO2 transport and does not affect blood pH.
• B. Bicarbonate has no significant role in erythrocytes.
• C. Bicarbonate only acts as a buffer and does not facilitate CO2 transport.
• D. Bicarbonate acts as a buffer to maintain blood pH and facilitates CO2 transport.

Answer: (D)