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: Medicine
[{'content': 'Major signs included by WHO for AIDS diagnosisa) Chronic diarrhea > 1 monthb) Chronic cough > 1 monthc) Chronic fever  > 1 month  d) Weight loss of at least 10% of body weighte) Generalized Lymphadenopathy \nSelect and explain. \nA. abc, B. acd, C. bc, D. bde', 'role': 'user'}, {'content': 'Answer: B \nExplanation: WHO CASE DEFINITION FOR AIDS SURVEILLANCE\n\nFor the purposes of AIDS surveillance an adult or adolescent (> 12 years of age) is considered to have AIDS if at least 2 of the following major signs are present in combination with at least 1 of the minor signs listed below, and if these signs are not known to be related to a condition unrelated to HIV infection.\n\nMajor signs (2 signs or more) :\n\nWeight loss of at least 10% of body weight\nChronic diarrhoea for> 1 month\nProlonged fever for> 1 month (intermittent or constant)\n\nMinor signs (1 or more) :\n\nA persistent cough for> 1 month\nGeneralized pruritic dermatitis\nHistory of herpes zoster\nOropharyngeal candidiasis\nChronic progressive or disseminated herpes virus infection\nGeneralized lymphadenopathy.\nThe presence of either generalized Kaposi sarcoma or cryptococcal meningitis is sufficient for the diagnosis of AIDS for surveillance purposes.\n\nEXPANDED WHO CASE DEFINITION FOR AIDS SURVEILLANCE:\n\nFor the purpose of epidemiological surveillance, an adult (> 12 years of age) is considered to have AIDS if a test for HIV antibody shows positive results, and one or more of the following are present:\n10% body weight loss or cachexia, with diarrhoea or fever, or both, intermittent or constant, for at least 1 month, not known to be due to a condition unrelated to HIV infection.\nCryptococcal meningitis.\nPulmonary or extra-pulmonary tuberculosis.\nKaposi sarcoma.\nNeurological impairment sufficient to prevent independent daily activities not known to be due to a condition unrelated to HIV infection (for example, trauma or cerebrovascular accident).\nCandidiasis of the oesophagus (which may presumptively be diagnosed based on the presence of oral candidiasis accompanied by dysphagia).\nClinically diagnosed life-threatening or recurrent episodes of pneumonia, with or without etiological confirmation.\nInvasive cervical cancer.', 'role': 'assistant'}]