You are designing a Windows Phone 7 application that uses multiple pages for the entry of user data. A user can freely navigate among the pages in the application at any time. The user can also perform actions that use a launcher or chooser object to select data to populate data entry fields. You need to recommend a way for page data to persist when the user navigates through the application. What should you recommend?
A.
Add a button to the page with a Click event that persists the page data to IsolatedStorage when the button is clicked.
B.
Add NavigatedTo and NavigatedFrom events that retrieve and store page data by using the State property of the PhoneApplicationService object when the events are executed.
C.
Add logic to the Application_Launching and Application_Closing events that retrieve and store page data to IsolatedStorage when the events are executed.
D.
Add logic to the Application_Deactivated and Application_Activated events that retrieve and store page data by using the State property of the PhoneApplicationService object when the events are executed.