Final answer:
The role that provides User1 with the required permissions to view ATP reports in the Threat management dashboard within a Microsoft 365 subscription is Security Operator.
Step-by-step explanation:
The role that provides User1 with the required permissions to view Advanced Threat Protection (ATP) reports in the Threat management dashboard within a Microsoft 365 subscription is Security Operator.
The Security Operator role in Microsoft 365 is specifically designed to allow users to view and manage security-related features and reports. This includes the ability to access and analyze ATP reports in the Threat management dashboard.
Other roles mentioned, such as Security Administrator, Compliance Administrator, and Threat Management, may have different levels of access and permissions, but the Security Operator role is the one that is directly related to viewing ATP reports in the Threat management dashboard.