The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Etching of dentin does not include:   (A) Removal of smear layer   (B) Exposure of collagen fibres   (C) Opening of dentinal tubules   (D) Increases surface energy
['(D) Increases surface energy <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Removal of smear layer \n (B) Exposure of collagen fibres \n (C) Opening of dentinal tubules \n (D) Increases surface energy <> possible answers', '  Etching of dentin does not include: <> context@']