The development team you manage has added new functionality to an application in the development
environment that improves the application currently running in the production SharePoint 2010 farm. The added functionality includes several custom Web Parts.
You need to create a plan to add the new functionality to the existing production SharePoint 2010 farm.
Which approach should you recommend?

A.
Create a new application that includes the Web Parts and deploy it to the farm as a .wsp package.

B.
Export the site hosting the Web Parts as a .stp template file. Change the template file and import the .stp file back into the production farm.

C.
Build the new functionality into a feature and use the Stsadm Upgrade command to update the application in the farm.

D.
Build the new functionality into a feature in a new solution package and deploy it to the production farm.