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
[{'content': 'Regarding color blindness true-a) Mainly congenitalb) Can be tested with Fansworth 100 hue testc) Ishihara chart test red/ green color blindnessd) Jerlin- Merlin cotton wool tests it \nSelect and explain. \nA. abc, B. bc, C. acd, D. bcd', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Most common type of colour blindness in congenital.\nFansworth munsell 100 hue test is the most sensitive test for both congenital and aquired colour defects.\nIshihara plates mainly used to screen congenital protanopes (red blind) and deutranopes (green blind).', 'role': 'assistant'}]