Jenny should work on the administration class to change the entry point of the application. This class consists of a method or member function to enter the application and a data file to provide access to contents of the application.
Explanation:
In order to change the way the application is entered, Jenny should work only on the administration class which in turn should be protected with a password because being a developer, she should be the only one having the authority to change certain methods. Administration class should only be accessed by her.