The following are multiple choice questions (with answers) about medical knowledge.   **Question:** For how long should NiTi files be submerged in NaOCl at 122-degree F to prevent damage to file corrosion   (A) 20 mins   (B) 45 mins   (C) 60 mins   (D) 2 hours
['(C) 60 mins <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) 20 mins \n (B) 45 mins \n (C) 60 mins \n (D) 2 hours <> possible answers', '  For how long should NiTi files be submerged in NaOCl at 122-degree F to prevent damage to file corrosion <> context@']