The following are multiple choice questions (with answers) about medical knowledge.   **Question:** The best stimulator of respiratory centre is:   (A) Decrease in arterial carbon dioxide level   (B) Increase in arterial carbon dioxide level   (C) Increase in arterial oxygen level   (D) None of the above
['(B) Increase in arterial carbon dioxide level <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Decrease in arterial carbon dioxide level \n (B) Increase in arterial carbon dioxide level \n (C) Increase in arterial oxygen level \n (D) None of the above <> possible answers', '  The best stimulator of respiratory centre is: <> context@']