Final answer:
The correct answer to the student's question about the activities involved in switching from an old to a new AIS is C. implementation. This includes installation, user training, data migration, testing, and establishing support structures.
Step-by-step explanation:
The successful switch from the old to the new Accounting Information System (AIS) is primarily associated with the C. implementation phase. This transition involves a series of activities that ensure the new system is correctly installed, users are trained, data is migrated, the system is tested, and support structures are put into place. Analysis pertains to understanding the current system's limitations and requirements for a new system, design involves planning the new system's architecture and functions, and operation is the stage where the system is used in everyday business activities.