<prompt> Patent formen ovale is due to failure of fusion of?Ostium primum with Endocardial cushionOstium primum with Ostium SecundumOstium primum with Septum primumSeptum primum with septum secundum  <response>: D i.e. Septum primum with septum secundumUnequal division of conus Gordis resulting from anterior displacement of conotruncal septum gives rise to Fallots tetralogyQ.- Ligamentum teres hepatis is remnant of umbilical vein leftQ and ligamentum aeriosum in adult is remnant of ductus aeriosusQ.Patent foramen ovale is dt failure of septum primum with septum secundumQ. 