This warning does not really make it clear that the user might be in the wrong perspective, but just states that no application project was selected. In this case, the user felt they were selecting the right application, but it was in the wrong perspective.
Due to the similarity of the layout of this perspective view with the "Project Explorer" perspective, it is unclear to the user that the wrong perspective is open, and so the user does not understand why the options for "Generate Linker Script," "Change Referenced BSP," and "C/C++ Build Settings" are gone when there is a right click on the C Project folders.
To resolve this, ensure that the Project Explorer Perspective is open.In order to open Project Explorer Perspective, select "Window" -> "Show View" -> "Project Explorer." The "Project Explorer" tabis now selectable in the view tabs. In this Project Explorer perspective, all the associated options for the application projectare available.