Which of the following is true about case-control study?

A case-control study is designed to help determine if an exposure is associated with an outcome (i.e., disease or condition of interest). In theory, the case-control study can be described simply. First, identify the cases (a group known to have the outcome) and the controls (a group known to be free of the outcome). Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 79