A 41-year-old woman with one healthy child presents with a 3-year history of an inability to conceive despite normal menstrual cycles. A biphasic basal body temperature cha is recorded. She denies having any sexually transmitted disease, and a hysterosalpingogram shows patent uterine tubes and a normal uterine cavity. Her husbands semen analysis is normal. In the presence of several normal test results for infeility, a laparoscopic examination of the pelvic cavity is scheduled. The physician performing the procedure carefully places the trocar lateral to the rectus abdominis muscle and its sheath to avoid injury to a major aery. What aery is being avoided?