This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
[{'content': 'Endometrium during proliferative phase appears as all except \nSelect and explain. \nA. Echogenic stratum basale, B. Trilaminar, C. Maximum thickness, D. Hypoechoic stratum functionate', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Endometrium achieves its maximum thickness during secretory phase.', 'role': 'assistant'}]