You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4.0 to develop an application.
You use the ADO.NET Entity Framework Designer to model entities.
You need to create a Plain Old CLR Object (POCO) class that can be used with the ObjectContext.CreateObject method to create a proxy.
What should you do?
A.
Create a custom data class that has a Protected constructor that does not have parameters.
B.
Create a custom data class in which all properties and methods are virtual.
C.
Create a custom data class that is abstract.
D.
Create a custom data class that is sealed.
Explanation:
Requirements for Creating POCO Proxies
(http://msdn.microsoft.com/en-us/library/dd468057.aspx)
Note that the question does not say that the custom model needs to support change tracking proxies or lazy loading proxies. Therefore, B is not a requirement.