The greatest concern for an IS auditor in this scenario is that the user department will manage access rights to the new accounting system. This could pose a significant risk of unauthorized access, segregation of duties violations, data tampering and fraud. The IS auditor should ensure that access rights are defined, approved and monitored by an independent function, such as IT security or internal audit. The other options are not as concerning as option C, as they can be mitigated by other controls or procedures. Data migration is an important part of the system replacement project, but it can be performed by another party or verified by the IS auditor. The timing of the replacement near year-end reporting is a challenge, but it can be managed by proper planning, testing and contingency plans. Testing performed by the third-party consultant is acceptable, as long as it is reviewed and validated by the IS auditor or another independent party. References: CISA Review Manual (Digital Version) 1, Chapter 3: Information Systems Acquisition, Development and Implementation, Section 3.4: System Implementation.