A22-year-old woman is brought to the emergency department because of a 2-day history of fever and severe vaginal bleeding. four days ago. she delivered a healthy male newborn spontaneously at term. her temperature is 38.1•c (100.6°f). pelvic examination shows an open cervi and heavy vaginal bleeding. ultrasonography of the uterus shows no retained placental tissue or large thrombi. if an operation is required to control the bleeding ligation of a branch of what arterie is most appropriate?