Which organism is identified by red acid-fast rods on smear and breadcrumb-like colonies on Lowenstein-Jensen medium after several weeks of incubation?

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Acid-fast bacilli on a smear point to organisms with mycolic acids in their cell walls, which resist decolorization and appear red with Ziehl-Neelsen staining. When such mycobacteria are cultured on Lowenstein-Jensen medium, they grow very slowly and typically form dry, crumbly, breadcrumb-like colonies after several weeks. This combination of red acid-fast rods and the characteristic slow, crumbly colony morphology on LJ is classic for the tuberculosis complex. Among the listed organisms, this pattern best matches Mycobacterium tuberculosis. Other options either do not grow on standard LJ medium, grow much faster, or show different colony appearances, so they don’t fit this description.