The following are multiple choice questions (with answers) about medical knowledge.   **Question:** True about Arrangement of hydroxyapatite crystals in Enamel rods?   (A) In center orientation of hydroxyapatite crystal is 0 degree   (B) Orientation of hydroxyapatite crystals at periphery is 45 degree   (C) Both   (D) None
['(C) Both <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) In center orientation of hydroxyapatite crystal is 0 degree \n (B) Orientation of hydroxyapatite crystals at periphery is 45 degree \n (C) Both \n (D) None <> possible answers', '  True about Arrangement of hydroxyapatite crystals in Enamel rods? <> context@']