This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
[{'content': 'Which pigment accumulates in brown atrophy of hea? \nSelect and explain. \nA. Melanin, B. Lipofuscin, C. Hemosiderin, D. Hemozoin', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Lipofuscin, or "wear-and-tear pigment," is an insoluble brownish-yellow granular intracellular material that accumulates in a variety of tissues (paicularly the hea, liver, and brain) as a function of age or atrophy.Lipofuscin represents complexes of lipid and protein that derive from the free radical-catalyzed peroxidation of polyunsaturated lipids of subcellular membranes. It is not injurious to the cell but is a marker of past free radical injury. The brown pigment, when present in large amounts, impas an appearance to the tissue that is called brown atrophy. Melanin is an endogenous, brown-black pigment that is synthesized by melanocytes and acts as a screen against harmful ultraviolet radiation.Hemosiderin is a hemoglobin-derived granular pigment that is golden yellow to brown and accumulates in tissues when there is a local or systemic excess of iron.( Robbins Basic Pathology, 9th edition, page 24 )', 'role': 'assistant'}]