The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Optimal landmark for termination of cleaning, shaping and obturation is   (A) Cementodentinal junction   (B) Apical constriction   (C) Minor diameter   (D) All of the above
['(A) Cementodentinal junction <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Cementodentinal junction \n (B) Apical constriction \n (C) Minor diameter \n (D) All of the above <> possible answers', '  Optimal landmark for termination of cleaning, shaping and obturation is <> context@']