Final answer:
The correct statement is that the direct approach is the riskiest because there is no safety net if the new system fails after the old one is replaced. The parallel system actually increases workload by operating two systems concurrently, and modular implementation can be combined with several approaches, not just the direct one.
Step-by-step explanation:
The statement that is true related to implementation approaches is: D. The direct approach is the riskiest of the three approaches. In the direct approach, also known as the Big Bang approach, an organization switches over from the old system to the new system on a set date. This approach is considered risky because there is no fallback if the new system fails; the old system is usually discarded, which can lead to significant disruptions if the new system does not work as intended.
The parallel system approach, on the other hand, involves running both the old and new systems concurrently for a period of time. This does not decrease employees' workload as they must manage both systems simultaneously, so statement A is incorrect. Statement B is also incorrect because the parallel approach maintains the operation of both systems during the conversion period rather than terminating one. As for statement C, this is inaccurate since modular implementation, which involves implementing the new system in phases or modules, can be combined with various approaches not just the direct approach for transitioning systems.