A primigravida is admitted to the labor area with ruptured membranes and contractions occurring every 2 to 3 minutes, lasting 45 seconds. After 3 hours of labor, the client's contractions are now every 7 to 10 minutes, lasting 30 seconds. The nurse administers oxytocin (Pitocin) as ordered. The expected outcome of this drug is:

A The cervix will begin to dilate 2 centimeters per hour. D Contractions will be every 2 minutes, lasting 60 to 90 seconds, with intrauterine pressure of 70 mm Hg. C The cervix will change from firm to soft, efface to 40% to 50%, and move from a posterior to anterior position. B Contractions will occur every 2 to 3 minutes, lasting 40 to 60 seconds, moderate intensity, resting tone between contractions.