The greatest concern for an IS auditor evaluating the access controls for a shared customer relationship management (CRM) system is that audit logging is not enabled. Audit logging is a process that records and tracks the activities and events that occur on a system, such as who accessed what data, when, how, and why.
Audit logging can help monitor and verify the compliance and effectiveness of the access controls, as well as detect and investigate any unauthorized or suspicious access or actions. Audit logging can also provide evidence and accountability for the security and integrity of the system and the data.
Without audit logging, the IS auditor would not be able to audit the access controls for the shared CRM system, as there would be no reliable or traceable records of the access history or patterns. Without audit logging, the organization would also not be able to identify or respond to any potential breaches or incidents that may compromise the confidentiality, availability, or accuracy of the CRM data. Without audit logging, the organization would also not be able to demonstrate or prove itscompliance with any applicable policies, regulations, or standards that may require audit logging for CRM systems.
Single sign-on is not enabled is not a great concern for an IS auditor evaluating the access controls for a shared CRM system, but rather a potential improvement or enhancement. Single sign-on is a process that allows users to access multiple systems or applications with one set of credentials, such as a username and password. Single sign-on can help simplify and streamline the user experience, as well as reduce the risk of password fatigue or compromise. However, single sign-on is not a mandatory or essential requirement for access controls, and it may also introduce some challenges or risks, such as dependency on a single point of failure or vulnerability.
Security baseline is not consistently applied is not a great concern for an IS auditor evaluating the access controls for a shared CRM system, but rather a minor issue or gap. Security baseline is a set of minimum security standards or requirements that apply to a system or application, such as password policies, encryption protocols, or firewall rules. Security baseline can help ensure that the system or application meets a certain level of security and compliance. However, security baseline is not a sufficient or comprehensive measure for access controls, and it may also need to be customized or adjusted according to the specific needs and risks of each system or application.
Complex passwords are not required is not a great concern for an IS auditor evaluating the access controls for a shared CRM system, but rather a common practice or recommendation. Complex passwords are passwords that are composed of a combination of different types of characters, such as letters, numbers, symbols, and cases. Complex passwords can help prevent or deter brute-force attacks or guessing attempts by making the passwords harder to crack or predict. However, complex passwords are not a guarantee or guarantee of security, and they may also have some drawbacks or limitations, such as user inconvenience, memorability issues, or reuse across multiple systems or applications.
References:
Customer Relationship Management Risks and Controls - CRM Simplified 1
Customer relationship management: A guide - Zendesk 2
How to Protect Your Customer Relationship Management (CRM) Data from Hackers 3 What is CRM? | A Definition by Salesforce 4

Unauthorized data modifications during conversion (D) are the most critical concern because they compromise data integrity, leading to inaccurate or corrupted information in the new system. Data migration should be performed with strict controls, including validation, reconciliation, and audit trails.
Other options:
Lack of online backups (A) is a risk but not as severe as compromised data integrity. Offline backups may still exist.
Undocumented change management (B) is a process deficiency but does not directly affect data accuracy.
Manual data conversion (C) increases risk but does not automatically indicate unauthorized changes.
Reference: ISACA CISA Review Manual, Information Systems Acquisition, Development, and Implementation

An IT service desk is a function that provides technical support and assistance to the users of an organization' s IT systems and services. An IT service desk typically handles issues such as software installation, hardware troubleshooting, network connectivity, password reset, system configuration,and user training. An IT service desk aims to ensure that the IT systems and services are available, reliable, secure, and efficient for the users.
One of the best indications that there are potential problems within an organization's IT service desk function is an excessive backlog of user requests. A backlog is a list of user requests that have not been resolved or completed by the IT service desk within a specified time frame. An excessive backlog means that the IT service desk is unable to meet the demand or expectations of the users, and that the users are experiencing delays, dissatisfaction, or frustration with the IT service desk.
An excessive backlog of user requests can indicate various problems within the IT service desk function, such as:
Insufficient staff, resources, or capacity to handle the volume or complexity of user requests Ineffective processes, procedures, or tools for managing, prioritizing, or resolving user requests Lack of skills, knowledge, or training among the IT service desk staff to deal with different types of user requests Poor communication, collaboration, or coordination among the IT service desk staff or with other IT functions or stakeholders Low quality, performance, or security of the IT systems or services that cause frequent or recurring user issues Therefore, an excessive backlog of user requests is the best indication that there are potential problems within an organization's IT service desk function.
References:
What is an IT Service Desk? Definition and Functions - Indeed
The Most Common IT Help Desk Issues - SherpaDesk
18 Common IT Help Desk Problems and Solutions - E-Pulse Blog