Correct option is A
Explanation-
Option a - Schistosoma mansoni - This is a Parasitic helminth (worm) . It is an extracellular parasite, found in blood vessels, not inside macrophages. It does not require macrophage survival for its life cycle.
Incorrect options-
Option b - Mycobacterium tuberculosis . This is a bacterium (cause of TB). It is a classic intracellular pathogen, survives and multiplies inside macrophages by inhibiting phagosome-lysosome fusion.
Option c - Listeria monocytogenes. This is a bacterium (foodborne pathogen). This bacterium invades macrophages, escapes into cytoplasm, and multiplies inside. It also uses actin-based motility for cell-to-cell spread.
Option d - Leishmania donovani . This is a protozoan parasite (causes visceral leishmaniasis) . This parasite is adapted to live and replicate inside macrophages, especially inside phagolysosomes.
