This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Metabolism of carbohydrate, Subject name: Biochemistry
Enzyme deficiency in Pompe's disease? 
Select and explain. 
A. Glycogen synthase, B. Liver debranching enzyme, C. Acid maltase, D. Muscle phosphorylase
C: Acid maltase
Answer: C: Acid maltase 
Explanation: Type Name Enzyme Deficiency Clinical Features II Pompe disease Lysosomal a1 - 4 and a1 - 6 glucosidase (acid maltase) Accumulation of glycogen in lysosomes: juvenile onset variant, Muscle hypotonia, Death from hea failure by age 2 Adult-onset variant, muscle dystrophy Reference: Harper; 30th edition; Table: 18-2; Page no: 179