This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gynaecological Diagnosis, Subject name: Gynaecology & Obstetrics
[{'content': 'Feature of post ovulatory endometrium on ultrasound is: \nSelect and explain. \nA. Single hyperechoic thin line, B. Three line sign, C. Prominent halo, D. Prominent posterior enhancement', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. is d, i.e. Prominent posterior enhancementRef: Transvaginal Ultrasound by Melvin G. Dodson 1st/ed, p86This is a very important QuestionIMPORTANT: The appearances of endometrium on transvaginal ultrasound during different stages of normal menstrual cycle has been summarized here.A. Just after menstruation (days 3-7)Single hyperechoic thin lines (central endometrial echo)B. At the time of ovulationHalo presentRelatively thin anterior posterior endometrial thickness (<6mm)No posterior enhancementQThree line sign.Q/Trilaminar appearanceC. Luteal phaseMaximum endometrial thicknessHyperechoic endometriumLoss of haloQLoss of three line signQProminent posterior enhancementQ', 'role': 'assistant'}]