Answer: JAD
Step-by-step explanation:
JAD is the joint application design system that is basically used in the RAD stage for collecting the users requirement.
It is basically used in the design and development of various types of application in the rapid application design more quickly. It is basically involve with the client and end users by a succession of various types of collaboration which is known as JAD session.
The joint application design basically involve with the continuous interaction with the end users for the development of the system.
All the remaining options does not involve with the RAD methodology that is why it is incorrect.
Therefore, JAD is the correct option.