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
Cofactor for Glycogen phosphorylase in Glycogenolysis is 
Select and explain. 
A. Thiamine pyrophospohate, B. Pyridoxal phosphate, C. Citrate, D. FAD
B: Pyridoxal phosphate
Answer: B: Pyridoxal phosphate 
Explanation: Glycogen phosphorylase removes glucose as glucose-6- phosphate from glycogen. It contains pyridoxal phosphate as prosthetic group.Ref: DM Vasudevan, 7th edition, page no: 124