<prompt> In a fetus highest oxygen concentration is found in?Inferior vena cavaSuperior vena cavaLeft ventricleAscending aoa  <response>: Among the following options, highest oxygen conc is found in IVC Saturation of Oxygen in fetal structures - Umbilical vein - 80 PO2 of 30-35 mm Hg Max. in entire body of fetus Inferior vena cava - 70 PO2 of 26-28 mm Hg Left ventricle - 65 Right Ventricle - 55-60 Umbilical aery - very low SVC - PO2 of 12-14 mm Hg 