How does the interaction between BPG and fetal hemoglobin affect oxygen transport during pregnancy?

• A. Fetal hemoglobin's low affinity for BPG increases its oxygen affinity, facilitating oxygen transfer from maternal blood.
• B. BPG has no effect on fetal hemoglobin's oxygen affinity.
• C. BPG increases fetal hemoglobin's oxygen affinity by binding to gamma subunits.
• D. BPG binds more strongly to fetal hemoglobin, reducing its oxygen affinity.

Answer: (A)