You are designing a Windows Presentation Foundation (WPF) application by using Microsoft .NET Framework 4 and Microsoft SQL Server 2008. The application runs successfully on a local client computer by using your user account. You deploy the database of the application to the production server. You configure the application connection string to use the Windows Authentication mode. You deploy the application to several client computers that use other applications on the network. The client computers access different databases on the production server by using the Windows Authentication mode. Users report that the application is not working and that they receive a database connection exception. You need to identify the source of the problem. What is the source of the problem?

A.
The database is currently blocked due to locks.

B.
The users do not have the correct database permissions.

C.
The users do not have valid SQL Server 2008 database logins.

D.
The client computers are not configured to use the network.