A Community Health Nurse Is Participating in a Case-Control Observational

A community health nurse is participating in a case-control observational study. Which statement best explains this type of study?

A) Description of patterns of occurrence of illness and injury in a population
B) Investigation of development of health-illness conditions over a long period of time
C) Studying of a cohort with evaluation of variables associated with the disease or injury
D) Comparison of persons with and without a health-illness condition