The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Water content in enamel by volume   (A) 2-3%   (B) 6-7%   (C) 20-25%   (D) 10-12%
['(B) 6-7% <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) 2-3% \n (B) 6-7% \n (C) 20-25% \n (D) 10-12% <> possible answers', '  Water content in enamel by volume <> context@']