You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. 
You create a Web form in the application by using the following code fragment. （Line numbers are included for reference only.）

You plan to create a client-side script code by using ASP.NET AJAX. 
You need to ensure that while a request is being processed， any subsequent Click events on the btnSubmit Button control are suppressed. 
Which code fragment should you insert at line 10？（）

You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. 
You write the following code fragment. 

You need to ensure that when you click the btnSubmit Button control， each Label control value is asynchronously updatable. 
Which code segment should you use？（）