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: Biochemistry
Niemann-pick disease is due to the disturbance in: 
Select and explain. 
A. Lipid metabolism, B. Protein metabolism, C. Carbohydrate metabolism, D. Mineral metabolism
A: Lipid metabolism
Answer: A: Lipid metabolism 
Explanation: Progressive lysosomal accumulation of glycosphingolipids in the central nervous system leads to neurodegeneration, storage in visceral cells can lead to organomegaly, skeletal abnormalities, pulmonary infiltration, and other manifestations. Such diseases are due to defect in lipid metabolism.