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': "Which one of the following is not a sign of early pregnancy? \nSelect and explain. \nA. Goodell's sign, B. Hegar's sign, C. Cullen's sign, D. Palmer sign", 'role': 'user'}, {'content': "Answer: C \nExplanation: Cullen's sign", 'role': 'assistant'}]