The following are multiple choice questions (with answers) about medical knowledge.   **Question:** ETDRS grading of vision is done for   (A) Endothelial count   (B) Corneal topography   (C) Primary open angle glaucoma   (D) Classification of diabetic retinopathy
['(D) Classification of diabetic retinopathy <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Endothelial count \n (B) Corneal topography \n (C) Primary open angle glaucoma \n (D) Classification of diabetic retinopathy <> possible answers', '  ETDRS grading of vision is done for <> context@']