This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
Neurotoxicity is seen with excess of 
Select and explain. 
A. Vitamin B6, B. Vitamin B12, C. Vitamin B2, D. Vitamin C
A: Vitamin B6
Answer: A: Vitamin B6 
Explanation: Neurotoxicity is seen with excess of Vit B6. Toxicity of pyridoxine: Pyridoxine is the only water-soluble vitamin with significant toxicity. Neurologic symptoms (sensory neuropathy) occur at intakes above 200 mg/day, an amount more than 100 times the RDA. Substantial improvement, but not complete recovery, occurs when the vitamin is discontinued. Reference: Lippincott Textbook of Biochemistry pg no. 378