Synthesize the information on fetal hemoglobin to explain how it facilitates oxygen transfer from maternal blood to fetal blood.

• A. Fetal hemoglobin's lower oxygen affinity prevents it from capturing oxygen from maternal blood.
• B. Fetal hemoglobin's structure is identical to adult hemoglobin, so it does not affect oxygen transfer.
• C. Fetal hemoglobin competes with maternal hemoglobin for oxygen, reducing transfer efficiency.
• D. Fetal hemoglobin's higher oxygen affinity allows it to effectively capture oxygen from maternal blood.

Answer: (D)