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: Ophthalmology
In a patient with suspected tubercular anterior uveitis the diagnosis is confirmed by: 
Select and explain. 
A. Positive Mantoux test, B. Associated findings suggestive of old systemic tuberculosis, C. A positive response to isoniazid test, D. All of the above
C: A positive response to isoniazid test
Answer: C: A positive response to isoniazid test 
Explanation: Ans. A positive response to isoniazid test