Answer:
A. reliable secondary data is both scarce and difficult to
Step-by-step explanation:
Primary data are data collected or retrieved from the source. These data are obtained directly by researchers from the source where the data emanate from. Examples of primary data are survey, interview, group discussion.
Secondary data are data collected by other people other than the source or user. Examples are reports, news paper articles, journals etc.
Most international researchers collects their own primary data because of the difficulty and scarcity of collecting reliable secondary data. Both types of data are important though but the difficulties in obtaining those reliable secondary data prompts the collection of primary data.
These researchers goes to the root or source of the data to be collected because their findings will eventually be relied upon by users like individuals, government, corporate organizations, schools etc. Relying on secondary data might be hard because they might have be tampered with or altered which may not reflect the true nature of the data.