Which of the following is the most likely effect of increased levels of red blood cell 2,3 diphosphoglycerate (2,3-DPG)?

The 2,3-bisphosphoglycerate (2,3-BPG) binds to the central cavity of the heme molecule and changes the configuration in favor of oxygen release. The other common factors that affect oxygen affinity are temperature and pH. The oxygen affinity of Hb is easily characterized by P50; the oxygen tension at which Hb is half-saturated.