You are answering a USMLE-style medical question. Question: A 25-year-old woman presents to the emergency department with abdominal pain. She states that she was walking up the stairs at work when she felt sudden and severe abdominal pain followed by nausea and vomiting. Her past medical history is non-contributory and she is not currently taking any medications. Her temperature is 99.7°F (37.6°C), blood pressure is 122/78 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for an absence of abdominal tenderness, a left adnexal mass, and left adnexal tenderness. A transvaginal ultrasound demonstrates free fluid surrounding the ovary with edema and the presence of doppler flow. A urinary pregnancy test is negative. The patient's symptoms persisted after ibuprofen and acetaminophen. Which of the following is the best next step in management? Options: A) Laparoscopy B) Laparotomy C) MRI of the pelvis D) Observation and serial abdominal exams Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.