Answer:
b. Fetal Hb binds oxygen more tightly than adult Hb.
Step-by-step explanation:
This is because Fetal Hb needs to draw oxygen more efficiently from the blood stream of mother which is a very difficult task. The more affinity binds the oxygen from the blood stream that is already bonded with Hb of mother This is the main reasons it has higher affinity than that of an adult Hb.
Additionally, speaking of myoglobin. A myoglobin always has more affinity to bind oxygen that that of a haemoglobin molecule.