Upon compiling the data, the researcher identifies a problem due to the fact that neither data source uses a unique ID number for each student. Which of the following best describes the problem caused by the lack of unique ID numbers?
A. Students who have the same name may be confused with each other.
B. Students who have the same grade point average may be confused with each other.
C. Students who have the same grade level may be confused with each other.
D. Students who have the same number of absences may be confused with each other.