This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
Which of the following is true about case-control study? 
Select and explain. 
A. Multiple outcomes can be studied, B. Rapid and inexpensive, C. Less prone to bias, D. Risky to subjects
B: Rapid and inexpensive
Answer: B: Rapid and inexpensive 
Explanation: 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