This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: nutrition and digestion, Subject name: Biochemistry
[{'content': 'Which of the following vitamins deficiency occurs exclusively in carnivores? \nSelect and explain. \nA. Thiamine, B. Niacin, C. Cobalamine, D. Vitamin C', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Rich sources are amla (Indian gooseberry) (700 mg/ 100 g), guava (300 mg/100 g), lime, lemon and green leafy vegetables.', 'role': 'assistant'}]