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
Among the given conditions the least infectious type of TB is seen in which of the following associations? 
Select and explain. 
A. Cavitary pulmonary disease, B. Laryngeal TB, C. Sputum with 1,00,000 AFB/ml, D. HIV patients with TB
D: HIV patients with TB
Answer: D: HIV patients with TB 
Explanation: The most infectious patients have cavitary pulmonary disease or, much less commonly, laryngeal TB and produce sputum containing as many as 105-107 AFB/mL. Persons with both HIV infection and TB are less likely to have cavitations, they may be less infectious than persons without HIV co-infection. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 1342