Which of the Following Is Not True About the Subscription

Which of the following is not true about the subscription monetizing technique?

A) It works by offering your application for free but charging a monthly payment for the service being offered by the application.
B) It works by offering your application as paid application for minimum amount and charging a monthly payment for the service being offered by the application.
C) It works by offering your application for free but charging a yearly payment for the service being offered by the application.
D) It works by allowing the user to pay once for the application download, then the user gets free updates.