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: Dental
[{'content': 'Groove sign is seen in – \nSelect and explain. \nA. Donovanosis, B. LGV, C. Chancroid, D. Genital herpes', 'role': 'user'}, {'content': "Answer: B \nExplanation: Groove sign of Greenblatt' is pathognomonic of LGV → when inguinal lymph nodes are enlarged, they are separated by Poupart's ligment, producing a groove.", 'role': 'assistant'}]