You are creating an ASP.NET application by using the .NET Framework 3.5.

The application will utilize the ASP.NET Profile provider to store user information in Microsoft SQL Server.

The provider must integrate with a custom table that stores each profile property in a separate column.

You need to create a custom Profile provider by extending an existing provider class that will result in the least amount of effort.

Which provider class should you extend?

A.
SettingsProvider

B.
ProfileProvider

C.
SqlMembershipProvider

D.
ProviderBase

Explanation:
To implement a profile provider, you create a class that inherits the System.Web.Profile.ProfileProvider abstract class.
The ProfileProvider abstract class in turn inherits the System.Configuration.SettingsProvider abstract class, which inherits the System.Configuration.Provider. ProviderBase abstract class. Because of this inheritance chain, in addition to the required members of the ProfileProvider class,you must implement the required members of the SettingsProvider and ProviderBase classes.
See also:http://msdn.microsoft.com/en-us/library/ie/0580x1f5.aspx