This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2017, Subject name: Pharmacology
Which of the following is an example of placebo? 
Select and explain. 
A. Herbal medication with no known effect, B. Physiotherapy, C. Sham surgery, D. Cognitive behavioral therapy
C: Sham surgery
Answer: C: Sham surgery 
Explanation: * In sham surgery, surgery is done without any purpose; we just open the abdomen in one person and close it, in other person appendix is removed; this is done to see whether appendectomy has any advantage.* Placebos (fake drug/dummy medicine) are used in clinical trials to compare the two treatments; it can't produce any effect. * Herbal medication can produce some effects.* Physiotherapy can also produce effects.