This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Ophthalmology
[{'content': 'Macular involvement is common in \nSelect and explain. \nA. Toxoplasma, B. Malaria, C. CMV, D. Syphilis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Decreased visual acuity may occur as a result of macular involvement or severe vitreous inflammation. ... An active toxoplasmic retinochoroiditis is whitish and moderately exudative with ill-defined borders and involves the macula in a majority of patients. Ref khurana 6/e', 'role': 'assistant'}]