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: Pharmacology
An anti–hypertensive drug that causes positive Coomb's test is: 
Select and explain. 
A. Methyldopa, B. Clonidine, C. Hydralazine, D. Sodium–nitropruside
A: Methyldopa
Answer: A: Methyldopa 
Explanation: None