This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Women Imaging, Subject name: Radiology
[{'content': 'Investigation preferred to Confirm intrauterine device in place with missing strings of IUD? \nSelect and explain. \nA. Pelvic X-ray, B. USG, C. CT-Abdomen, D. MRI-Pelvis', 'role': 'user'}, {'content': 'Answer: B \nExplanation: - Ultrasound Preferred modality for assessing an IUD Properly placed IUD may be visualized as a straight hyper echoic structure in the endometrial canal of the uterus and the arms of the IUD extending laterally at the uterine fundus. - Ultrasound is appropriate for initial evaluation and can provide answers to clinical questions related to the IUD. - It easily helps determine whether an IUD is correctly positioned and can often help identify IUD related complications. - Three dimensional (3D) US is gaining recognition for its role in imaging IUDs.', 'role': 'assistant'}]