The correct answer is A. gpedit.msc, which opens the Local Group Policy Editor. Group Policy allows administrators to configure and enforce security-related settings, including screensaver timeout, password protection, and automatic locking, across systems or user accounts.

According to the Quentin Docter – CompTIA A+ Complete Study Guide, Group Policy is commonly used to enforce security policies such as inactivity timeouts, especially in departments handling sensitive data like finance or HR.

The Travis Everett & Andrew Hutz – All-in-One Exam Guide explains that screensaver timeout settings can be configured under User Configuration → Administrative Templates → Control Panel → Personalization, ensuring systems lock automatically after a defined period of inactivity.

The Mike Meyers / Mark Soper Lab Manual reinforces that tools like certmgr.msc manage certificates, devmgmt.msc manages hardware devices, and perfmon.msc monitors system performance. None of these tools control user security policies.

Because the requirement is to enforce a shorter screensaver timeout for security, Group Policy Editor is the correct and professional tool, making A the correct answer.