True about Ghons focus:: (A) Left apical parenchymal lesion, (B) Right apical parenchymal lesion, (C) Subpleural caseous lesion in right upper lobe, (D) Subpleural caseous lesion just above or below interlobar fissure.
Answer is D. Inhaled tubercule bacilli implanted in the distal air spaces of the lower pa of upper lobe or upper pa of lower lobe ,close to the pleura lead to formarion of ghons focus. Primary complex of tuberculosis consists of 3 components. Pulmonary compound Draining lymphnodes Caseating hilar lymphnode Caseous holar lymphadenopathy is associated with ghon complex and not ghon focus.(ref Robbins 8th/370,9/e p374)