HOTSPOT
You are developing an application that includes a Windows Communication Foundation
(WCF) service. The service includes a custom TraceSource object named ts and a method
named DoWork. The application must meet the following requirements:
Collect trace information when the DoWork() method executes.
Group all traces for a single execution of the DoWork() method as an activity that can be
viewed in the WCF Service Trace Viewer Tool.
You need to ensure that the application meets the requirements.
How should you complete the relevant code? (To answer, select the correct code segment
from each drop-down list in the answer area.)
Answer: 
11222
no, its:
12122
Can you please explain why it is 12122. In solution with 11222 ts.TraceEvent(TraceEventType.Start,0,”Start”) is used after changing the ActivityID.
Here are some examples: http://www.codeproject.com/Articles/185666/ActivityTracerScope-Easy-activity-tracing-with
Based on this ref the solution should be 11222
For ActivityTracing:
https://msdn.microsoft.com/en-us/library/system.diagnostics.sourcelevels(v=vs.110).aspx