During childbirth, the hormone oxytocin stimulates the smooth muscles of the uterus to contract; however, smooth muscles lining the digestive tract are not affected by oxytocin. Which statement correctly explains this scenario?

A) Smooth muscles of the digestive tract do not contain receptors for oxytocin.
B) Endocrine hormones such as oxytocin do not travel through the blood, so they do not make contact with digestive tract muscles.
C) The digestive tract muscles of the mother's body are temporarily paralyzed by the anti- pain medications administered during labor.
D) Oxytocin is a local hormone released by the uterus, so other muscles do not receive its signals.
E) Oxytocin is released by the fetus and diffuses into the amniotic fluid inside the uterus. Therefore, only uterine muscles are stimulated.