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
Which of the following vitamins deficiency occurs exclusively in carnivores? 
Select and explain. 
A. Thiamine, B. Niacin, C. Cobalamine, D. Vitamin C
D: Vitamin C
Answer: D: Vitamin C 
Explanation: Rich sources are amla (Indian gooseberry) (700 mg/ 100 g), guava (300 mg/100 g), lime, lemon and green leafy vegetables.