Crowing. which occurs when the newborns head or presenting part appears at the vaginal opening. occurs during the second stage of labor.Option A: During the first stage of labor. cervical dilation and effacement occur.Option C: During the third stage of labor. the newborn and placenta are delivered.Option D: The fourth stage of labor lasts from 1 to 4 hours after birth. during which time the mother and newborn recover from the physical process of birth and the mothers organs undergo the initial readjustment to the nonpregnant state.