You are responsible for ensuring that only a select group of users can access sensitive financial data in JIRA. Which aspect of JIRA's user management system would you focus on?

Issue Security Schemes: Issue Security Schemes in JIRA enable you to restrict access to specific issues based on user roles or groups. By configuring the appropriate issue security scheme, you can ensure that only authorized users have access to sensitive financial data, thus maintaining data confidentiality and security within the JIRA system.