This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carbohydrates, Subject name: Biochemistry
Giucose-6-phosphatase is absent or deficient in: 
Select and explain. 
A. Von Gierke's disease, B. Pompe's disease, C. Cori's disease, D. McArdle's disease
A: Von Gierke's disease
Answer: A: Von Gierke's disease 
Explanation: Ans. A. Von Gierke's diseaseGlycogen Storage Diseases (GSD's) are caused due to deficiency of certain enzymes:TypeName of the diseaseEnzyme deficientClinical FeaturesType IVon Gierke's diseaseGlucose-6-PhosphataseHypoglycemia, Ketosis, Hyperuricemia, HepatomegalyType IIPompe's diseaseLysosomal a-1,4 & 1,6 glucosidaseAccumulation of glycogen in lysosomes, heart failureType IIICori's diseaseDebranching enzymeAccumulation of branched polysaccharideType IVAndersen's diseaseBranching enzymeHypoglycemia, Hepatic failure, Liver Cirrhosis, AscitesType VMe. Ardle's diseaseMuscle phosphorylaseMuscle cramps on exercise, Pain in muscle, weakness and stiffness of muscle.Type VIHer's diseaseLiver phosphorylaseHypoglycemia, High glycogen content in liver.Type VIITarui's diseasePhosphofructokinase in RBC & MuscleAs in type VType VIIIHepatic phosphorylase kinase deficiencyLiver phosphorylase kinaseAs in Type VI