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': "20 years old female came with complaint of a palpable painless mass in right breast. On examination, mass was mobile and hard in consistency. Ultrasound of right breast was performed . Most likely diagnosis is? \nSelect and explain. \nA. Breast cyst, B. Ductal papilloma, C. Fibroadenoma, D. Phylloid's tumour", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ultrasound shows a well-defined hypoechoic lesion seen in right breast . Given the clinical history and age of the patient, most likely diagnosis is fibroadenoma . Breast cyst is anechoic on USG.', 'role': 'assistant'}]