This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2018, Subject name: Pharmacology
Which of the following anti-tubercular drug can cause ophthalmological toxicity? 
Select and explain. 
A. Isoniazid, B. Rifampicin, C. Ethambutol, D. Pyrazinamide
C: Ethambutol
Answer: C: Ethambutol 
Explanation: Ethambutol side effect: causes Red Green color blindness (Ophthalmological toxicity) Isoniazid side effects: Neurotoxicity, Hepatotoxicity. Pyrazinamide side effects: Hyperuricemia (gouty ahritis). Rifampicin side effects: Hepatotoxicity, orange red urine and tears etc.