Secondary data, which is pre-existing and available in published formats, is particularly advantageous because:

A) Data that is not firsthand must be properly cited and referenced to be admissible.
B) You must locate it in hard copy at a library and then photocopy the relevant parts for your research.
C) It is readily accessible, quick, and easy to obtain in contemporary times.
D) Reports, articles, and conference papers are not considered valid sources of primary data.