The following are multiple choice questions (with answers) about medical knowledge.   **Question:** Mean and standard deviation can be worked out only if data is on -   (A) Interval/Ratio scale   (B) Dichotomous scale   (C) Nominal scale   (D) Ordinal scale
['(A) Interval/Ratio scale <> answer', 'The following are multiple choice questions (with answers) about medical knowledge. <> instruction', '(A) Interval/Ratio scale \n (B) Dichotomous scale \n (C) Nominal scale \n (D) Ordinal scale <> possible answers', '  Mean and standard deviation can be worked out only if data is on - <> context@']