单项选择题 You are developing a user control for Windows Presentation Foundation (WPF) application. The user control contains a button. Both the user control and the hosting control must receive the button click event. You need to ensure that the user control responsd to the button click event before hosting control responds to the event. What should you do ?（）

单项选择题 You are developing a Windows Presentation Foundation (WPF) application. You configure PresentationTraceSource to track errors in a bound TextBox control in the application. You need to choose the window that the Trace information is sent to Which Visual Studio window should you select ?（）

单项选择题 You are developing a Windows Presentation Foundation (WPF) application that display pricing and inventory. List boxs ItemsSource property has decimal and string types. Decimals represent price and strings represents the folowing markup is defined as follows. You need to ensure that data templates are used to format the strings without changes and the decimals as .. Which markup segment should you insert at line 05 ?（）