Which conversion method involves running the old and new systems simultaneously?

The selected answer is correct because parallel conversion is a method where both the old system and the new system are operated at the same time for a certain period. This approach allows users to compare the outputs of the two systems, ensuring that the new system accurately replicates or improves upon the functionalities of the old system before completely transitioning to it. By running them simultaneously, organizations can identify any discrepancies or issues in real-time, providing an opportunity to address problems without disrupting operations.

In contrast, pilot conversion involves rolling out the new system to a limited user group first, enabling a test phase before organization-wide implementation. Phased conversion means that the system is implemented in stages, rather than all at once, which allows for gradual adaptation but does not involve running both systems simultaneously. Direct conversion, on the other hand, entails shutting down the old system and immediately switching to the new one, which can carry higher risks if the new system has not been thoroughly tested. Each of these methods has its advantages and disadvantages, but parallel conversion specifically emphasizes the dual operation of both systems for enhanced reliability during the transition.