Final answer:
The uterus is retracted posteriorly due to the uterine arteries, which are branches of the internal iliac artery and are responsible for the positioning of the uterus within the pelvis.
Step-by-step explanation:
The pelvis contains several structures of the female reproductive system, including the uterus. In relation to the positioning of the uterus due to arterial influence, option B) Posteriorly due to the uterine arteries is the correct answer. The uterine arteries, which are branches of the internal iliac artery, supply blood to the uterus and are responsible for the positioning of the uterus within the pelvis. The ovarian arteries, on the other hand, supply blood to the ovaries, the uterine tubes, and the uterus and are located within the suspensory ligament of the uterus. These arteries anastomose with the uterine arteries but do not play a direct role in the anterior-posterior positioning of the uterus.