<prompt> A patient, diagnosed with rheumatoid arthritis, was on medications. After 2 years, developed blurring of vision and was found to have corneal opacity. Which of the following drug most likely causes that?SulfasalazineChloroquineMethotrexateLeflunomide  <response>: Salient Adverse Effects of DMARDs:DrugAdverse effectsGold Diarrhea Taste disturbances Alopecia DermatitisLeflunomide Diarrhea Hypokalemia Weight loss Alopecia Increased incidence of respiratory infections Raised liver enzymesNatalizumab Progressive multifocal leukoencephalopathyMethotrexate Bone marrow depression Mucositis Hepatotoxicity Increased incidence of respiratory infectionsSulfasalazine Neutropenia Thrombocytopenia Hepatitis Reversible infertility in maleChloroquine Bulls eye retinopathy Less with hydroxychloroquine Rash Greying of hair Irritable bowel syndrome Myopathy and Neuropathy 