The most important consideration when selecting an external service provider for outsourcing the payroll function is the internal controls to ensure data privacy. The payroll function involves processing and storingsensitive personal and financial information of the employees, such as salaries, taxes, benefits, bank accounts, etc. This information needs to be protected from unauthorized access, disclosure, modification, or loss, as it may result in legal, regulatory, reputational, or financial consequences for the organization and the employees. Therefore, the external service provider should have adequate internal controls, such as encryption, access control, backup, logging, monitoring, etc., to ensure data privacy and compliance with the organization’s policies and standards. Disaster recovery plan, right to audit, and transparency ofKPIs are also important considerations when selecting an external service provider, but they are not as important as internal controls to ensure data privacy. References = Risk and Information Systems Control Study Manual, 7th Edition, Chapter 5, Section 5.2.1.2, page 2461

1: ISACA Certified in Risk and Information Systems Control (CRISC®) Exam Guide, Answer to Question 648.