Case studies typically "consist of in-depth and detailed examinations of specific 'units’." They focus on an individual, group, organization, or event to provide a comprehensive understanding of the subject in question.
The other options provided refer to different research methods or approaches. For example:
- Collecting information on a large number of individuals is more aligned with surveys or quantitative research methods.
- Making a story about a person's life suggests a biographical approach or narrative analysis.
- A scientific and systematic search for pertinent information on a specific topic is representative of literature reviews or systematic reviews rather than case studies specifically.
So, the correct statement about case studies is the first one.