Which of the Following Statements Is True with Regard to "Missing

Multiple Choice

Which of the following statements is true with regard to "missing data" in existing statistics research.

A) Missing data is rarely a serious problem when using existing document/statistics research.
B) Missing data is fairly easy to control when using existing document/statistics research.
C) Missing data are something that researchers do not concern themselves over
D) Missing data is a serious problem that often plagues researchers using existing document/statistics research.