A multigravida, full-term, laboring client complains of "back labor." Vaginal examination reveals that the client's cervix is dilated 3 cm with 50% effacement, and the fetal head is at -1 station. Which action should the nurse implement?

A. Ambulating between contractions can help labor progress but may not provide immediate relief for back labor pain. B. Turning to a lateral position may improve comfort and fetal positioning, but it is less effective for directly addressing intense sacral pain. C. Preparing the operating room is unnecessary; there is no indication for a cesarean delivery at this stage of normal labor. D. Applying counter-pressure to the sacral area is the best intervention for back labor, which often occurs with occiput posterior fetal positioning. The pressure helps relieve discomfort caused by the fetal head pressing against the sacrum.