This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
Routine examination of a 17 years old asymptomatic boy reveals sho PR interval, and delta wave on ECG. The least effective measure for the boy would be: 
Select and explain. 
A. Hotter monitoring, B. Treadmill stress test, C. Beta blocker, D. Reassurance
B: Treadmill stress test
Answer: B: Treadmill stress test 
Explanation: Ans.b. Tredmill stress testThis is a case of WPW syndrome. There is no use all treadmill test in these cases as results are often misleading.Holter monitoring would be indicated to detect the development of any arrythmias. Beta-blockers have also been used in asymptomatic cases only as a preventive therapy against the development of PSVT.