input: The following are multiple choice questions (with answers) about medical knowledge.   **Question:** The function of posterior palatal seal is:   (A) To aid in balanced occlusion   (B) To aid in insertion and removal of complete denture   (C) To ensure a complete seal thus helping in retention of a denture   (D) Retention of mandibular denture by sealing its posterior margin.
output: ['(C) To ensure a complete seal thus helping in retention of a denture <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) To aid in balanced occlusion  (B) To aid in insertion and removal of complete denture  (C) To ensure a complete seal thus helping in retention of a denture  (D) Retention of mandibular denture by sealing its posterior margin. <> possible answers', '  The function of posterior palatal seal is: <> context']