input: The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Which of the following is common to both zinc oxide eugenol cement and polycarboxylate cement?   (A) Polyacrylic acid is liquid   (B) Chemical bond to tooth structure   (C) Chelation   (D) Substitution of eugenol by EBA to increase strength of cement
output: ['(C) Chelation <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Polyacrylic acid is liquid  (B) Chemical bond to tooth structure  (C) Chelation  (D) Substitution of eugenol by EBA to increase strength of cement <> possible answers', '  Which of the following is common to both zinc oxide eugenol cement and polycarboxylate cement? <> context']