You are designing an n-tier Windows application by using Microsoft .NET Framework 4,
Microsoft Visual Studio 2010, and Microsoft SQL Server 2008. The application will replace
an existing client/server application. The existing application was created by using Microsoft
Visual Basic 6.0 and consists of a series of COM components that access a SQL Server
database. You plan to move the existing COM components into a Windows Communication
Foundation (WCF) tier. You need to ensure that the COM components can be replaced
without impacting the existing user interface (UI) tier. You also need to ensure that the COM
components can be replaced separately. What should you do?
A.
Create a common assembly on the UI tier of the new application to interface with the
COM components.
B.
Create a common assembly on the WCF tier of the new application to interface with the
COM components.
C.
Use .NET COM Interop on the client tier to interact directly with the COM components
until they are replaced by the managed code.
D.
Convert the Visual Basic 6.0 source code to managed code by using the Visual Studio
converters. Use these code components on the client/server application until they are
replaced individually with the new permanent managed code functionality.
Explanation: