Which of the following is a built-in security component of Windows 10?

User Account Control (UAC) is a built-in security feature of Windows 10 designed to prevent unauthorized changes to the operating system. By prompting users for permission or an administrator’s password when applications try to make changes that require administrative access, UAC helps to mitigate the risk of malware and untrusted applications altering system settings without user consent. This proactive approach to security ensures that users are aware of actions that could impact the integrity and safety of their system.

In contrast, Firefox is a web browser and does not serve as a security component of the operating system itself. Active Directory is a directory service used for managing permissions and access to network resources in a Windows domain environment, but it is not a built-in security feature of the individual Windows 10 operating system. Multi-Factor Authentication (MFA) is a security measure that adds an additional layer of protection by requiring more than one form of verification for access, but it is not specifically a built-in component of Windows 10; it can be implemented through various services and applications.