Which of the following is/are true regarding fetal hemoglobi…

Which of the following is/are true regarding fetal hemoglobin?I.   Fetal hemoglobin has a lower affinity for oxygen as compared to adult hemoglobin.II.  Fetal hemoglobin will shift the oxyhemoglobin dissociation curve to the left.III. Fetal hemoglobin will shift the oxyhemoglobin dissociation curve to the right.IV. Fetal hemoglobin will have a higher oxygen carrying capacity as compared to adult hemoglobin.