A selection screen for prompting a user to select a file selection method and including at least first and second display items for selecting a file selection method is displayed. If the first display item is selected, a screen for a file selection function provided by the application is displayed, and a file selected through the screen is determined as a file to be processed. If the second display item is selected, the file selection function provided by the OS is invoked, and a file selected through the file selection screen provided by the OS is determined as a file to be processed. Data based on the file is transmitted to the image processing apparatus.