Which of the following statements bellow is true? And why pls explain briefly !
A. HbF has the same molecular structure as Hb, which consists of two alpha chains and two beta chains.
B. HbF has a different molecular structure with Hb; HbF has no alpha chains.
c. HbS differs from Hb only in the composition of the primary structure
D. HbS binds less oxygen than Hb but more than HbF.
( Hbf = fetal hemoglobin) (Hbs = Sickle cell hemoglobin) (HB= normal hemoglobin)