You are answering a USMLE-style medical question. Question: A 29-year-old woman presents to her OB/GYN for a preconception visit. She wishes to become pregnant within the next several months. A thorough history reveals that the patient suffers from phenylketonuria (PKU). She recalls being instructed by prior physicians to follow a diet that avoids certain foods; however, she admits to not being complaint with these recommendations. Laboratory testing reveals a plasma phenylalanine level of 20.2 mg/dL (normal range <2 mg/dL). Which of the following is the most appropriate response to this patient? Options: A) Improved PKU treatment will decrease the risks of spontaneous abortion and intrauterine fetal death B) 3 months prior to conception, begin a restricted diet to lower phenylalanine levels to below 6 mg/dL C) Begin a phenylalanine-restricted diet in your first trimester to reduce the risk of fetal morbidity D) Your current phenylalanine levels do not pose a risk to any future pregnancy Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.