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
[{'content': 'The following enzyme activity is measured in Beriberi: \nSelect and explain. \nA. Decarboxylase, B. Deaminase, C. Transketolase, D. Transaminase', 'role': 'user'}, {'content': 'Answer: C \nExplanation: In thiamine deficiency transketolase activity in erythrocytes is decreased. Measures of RBC transketolase is a reliable diagnostic test for thiamine deficiency. Beriberi is caused by thiamine deficiency. Ref: Clinical Laboratory Medicine, 2nd Ed, Page 322', 'role': 'assistant'}]