You are answering a USMLE-style medical question. Question: A 25-year-old primigravida is admitted to the hospital at 36 weeks gestation after a generalized tonic-clonic seizure. She is conscious, but lethargic and complains of a headache that started 2 hours prior to the seizure. She denies alcohol intake or drug use. She has no history of convulsive disorders and the antepartum course has been unremarkable. She was compliant with the recommended prenatal care and her last prenatal visit was 2 weeks ago. She has gained 2 kg (4.4 lb) since her last visit. The blood pressure was 160/90 mm Hg, the heart rate was 79/min, the respiratory rate was 14/min, and the temperature was 37.0℃ (98.6℉). The physical examination shows leg and perineal edema. The neurologic examination is significant for symmetric upper and lower extremity hyperreflexia and ankle clonus. Which of the following laboratory findings would be most common in this patient? Options: A) Elevated transaminases B) Leukocytosis C) Hyponatremia D) Proteinuria Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.