Which of the Following Is TRUE

Which of the following is TRUE?

A) It is not uncommon for secondary data to be expressed in units different from those deemed most appropriate for the project at hand.
B) Situations in which existing secondary data are ill-suited for the research problem at hand generally do not arise.
C) Secondary data are particularly appropriate when current, up-to-the-minute information is required.
D) The most fundamental rule in using secondary data is to always verify important information with at least two secondary data sources or with primary data.
E) They are all false.