This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition, Subject name: Pediatrics
[{'content': 'Keshan disease is caused by deficiency of: \nSelect and explain. \nA. Thiamine, B. Zinc, C. Selenium, D. Proteins', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. C. Selenium* Selenium is a constituent of glutathione peroxidase, an antioxidant in red blood cells and other tissues.* Glutathione peroxidase scavenges free Hydro peroxidases generated during fatty acid oxidation, thus protecting the cell from damage due to free radical formation.* Severe deficiency is the major cause of Keshan disease, which presents as cardiomyopathy in young children. Skeletal myopathies have also been reported.* Mild deficiency is associated with macrocytosis and loss of hair pigment.', 'role': 'assistant'}]