What security feature automatically locks inactive accounts after a period?

The feature that automatically locks inactive accounts after a specified period is found within the account sign-in security settings in the Admin console. This mechanism is crucial for enhancing security, as it helps to prevent unauthorized access to accounts that have not been used for a certain length of time. By locking these accounts, organizations can mitigate the risks associated with stale accounts that could be targets for malicious activities.

The other choices do not address the automatic locking of inactive accounts. Two-Factor Authentication settings bolster account security by requiring an additional verification step during sign-in but do not manage inactivity. Firewall configurations are related to controlling network traffic and protecting the network from unauthorized access instead of managing account statuses. Device management settings focus on overseeing and enforcing policies on devices accessing organizational resources rather than directly locking accounts due to inactivity.