input: The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Bonding agents have hydrophilic and hydrophobic groups. The hydrophobic group binds which structure?   (A) Calcium in enamel   (B) Hydroxyapatite group in hard tissue   (C) Resin in restoration   (D) Collagen in dentin
output: ['(C) Resin in restoration <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Calcium in enamel  (B) Hydroxyapatite group in hard tissue  (C) Resin in restoration  (D) Collagen in dentin <> possible answers', '  Bonding agents have hydrophilic and hydrophobic groups. The hydrophobic group binds which structure? <> context']