Which of the following is not an example of a Web portal?

A(n) ________ is particularly appropriate for providing services that disparate objects have in common.

a) abstract class b) concrete class c) interface d) None of the above.

After making a change to a program and attempting to re-run it, you get an error message stating that changes are not allowed. What can you do to clear the error?

A. You must close the IDE and re-open it. B. You must press F4 to run the application. C. The application store has been corrupted, you must reinstall Visual Studio. D. You must close the previous execution of the program, then you can attempt to re-run.