<prompt> A pediatric surgeon is resecting a possible malignant mass from the liver of a neonate with cerebral palsy. The surgeon divides the round ligament of the liver during surgery. A fibrous remnant of which of the following fetal vessels is severed?Ductus venosusDuctus aeriosusLeft umbilical veinRight umbilical vein  <response>: The left umbilical vein becomes the round ligament of the liver after bih. The right umbilical vein did not leave a fibrous remnant because it was degenerated during the early embryonic period. The ductus venosus forms the ligamentum venosum; the ductus aeriosus forms the ligamentum aeriosum; Umbilical aery forms the medial umbilical ligament. 