When would it be acceptable to consciously omit specific students from an action research project in a classroom?

Question

Quizplus · Accepted Answer

The Answer is The answer is when a convenience sample is used, or when a purposive sample is selected and participants who are known to represent the research concepts are selected for inclusion. An example would be when the research project applies only to athletes in a high school, for instance, or when it deals with a subject specifically meant for female students.

When Would It Be Acceptable to Consciously Omit Specific Students