Which One of the Following Statements Is Correct Concerning Ratio

Which one of the following statements is correct concerning ratio analysis?

A) A single ratio is often computed differently by different individuals.
B) Ratios do not address the problem of size differences among firms.
C) Only a very limited number of ratios can be used for analytical purposes.
D) Each ratio has a specific formula that is used consistently by all analysts.
E) Ratios can not be used for comparison purposes over periods of timE.