You are answering a USMLE-style medical question. Question: A 31-year-old woman, gravida 2, para 1, at 32 weeks' gestation presents to the emergency department for clear vaginal discharge that started roughly 26 hours ago. Her pregnancy has been uncomplicated. Her first child was born at term by vaginal delivery. She has no history of any serious illnesses. She does not drink alcohol or smoke cigarettes. Current medications include vitamin supplements. Her temperature is 37.2°C (98.9°F), pulse is 70/min, respirations are 18/min, and blood pressure is 128/82 mm Hg. Speculum examination demonstrates clear fluid at the cervical os. The fetal heart rate is reactive at 160/min with no decelerations. Tocometry shows uterine contractions. Nitrazine testing is positive. She is started on indomethacin. Which of the following is the most appropriate next step in management? Options: A) Administer ampicillin and perform amnioinfusion B) Administer ampicillin and progesterone C) Administer betamethasone, ampicillin, and proceed with cesarean section D) Administer betamethasone, ampicillin, and proceed with induction of labor Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.