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: Surgery
Drug induced portal hypertension is seen with - 
Select and explain. 
A. Vitamin A toxicity, B. Methotrexate, C. Aldomet, D. Valproic acid
A: Vitamin A toxicity
Answer: A: Vitamin A toxicity 
Explanation: Normal doses of vitamin A are not associated with liver injury or liver test abnormalities, but higher doses can be toxic
Mechanism of Injury
• Excess vitamin A is stored in stellate cells in the liver and accumulation can lead to their activation and hypertrophy, excess collagen production, fibrosis and liver injury.
• Serum bilirubin is typically only mildly elevated.
• Liver biopsy is diagnostic