The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Strength of collagen is due to:   (A) Hydroxy glycine   (B) Glycine   (C) Praline   (D) Hydroxyproline
['(D) Hydroxyproline <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Hydroxy glycine \n (B) Glycine \n (C) Praline \n (D) Hydroxyproline <> possible answers', '  Strength of collagen is due to: <> context@']