Adjusting the brightness directly from the system tray provides a quick and straightforward method for users to control screen brightness directly from the Windows interface.
Option A is incorrect as color calibration affects color output but not the brightness level of the display Option B is incorrect as the screen saver settings do not impact the ongoing brightness levels of a display Option D is incorrect as updating graphics drivers is not directly related to adjusting screen brightness settings

Correct Answer. C. df -h The df -h command (disk free) provides concise information about each mounted filesystem, including total space, used space, free space, and mount points, all formatted in human-readable form (e.g., GB, MB).
Option A is incorrect because top primarily monitors CPU and memory usage, not disk space.
Option B is incorrect because du -sh * shows the disk usage of files and directories in the current directory, which is useful but not as comprehensive for checking all disk space on the server.
Option D is incorrect because mount displays mounted filesystems, not their disk usage statistics.

Printing the recovery key and storing it securely (such as in a safe) protects against digital theft and ensures the user has physical access to the key when needed.
Option A is incorrect because while a USB drive is a viable option, it can be lost or damaged, posing a risk of loss Option B is incorrect because relying solely on a manufacturer's cloud service could be risky if the service experiences downtime or data loss Option D is incorrect because email accounts can be compromised, making it a less secure method for storing sensitive recovery keys

Correct Answer. B. Baud rate The baud rate is a critical setting for serial port configurations, as it determines the speed at which data is transmitted between devices. Incorrect baud rate settings can prevent effective communication between devices, leading to data loss or communication failures.
Option A is incorrect because resolution settings are relevant for video outputs and have no bearing on serial communication.
Option C is incorrect because brightness settings affect visual display units, not serial data transmission.
Option D is incorrect because USB compatibility concerns digital data ports and interfaces, not serial communication parameters.

Correct Answer. B. ipconfig /release followed by ipconfig /renew Using ipconfig /release followed by ipconfig /renew effectively refreshes the IP address by releasing the currently assigned IP address and requesting a new one from the DHCP server, potentially resolving IP-related connectivity issues.
Option A is incorrect. ipconfig /flushdns clears the DNS resolver cache but does not affect the IP address assignment.
Option C is incorrect. ipconfig /all displays detailed information but does not change or refresh IP settings.
Option D is incorrect. ipconfig /displaydns shows the contents of the DNS client resolver cache, providing no functionality for addressing IP configuration issues.