Which command is used to check video settings on a Linux system?

The command utilized to check video settings on a Linux system is xrandr. This tool is specifically designed to manage and query the X Window System display settings and is essential for handling display outputs, such as monitors and projectors. By using xrandr, users can see the current display configurations, available resolutions, refresh rates, and even make adjustments to these settings dynamically.

In contrast, the other options serve different functions. The lsmod command shows the currently loaded kernel modules, which may include drivers for graphics hardware but does not provide details about display settings. The lspci command lists all PCI devices on the system, including graphics cards, but again does not provide direct video settings or display configurations. Finally, dmesg displays kernel-related messages, which may include information about graphics hardware being initialized, but it is not focused on checking or configuring video settings the way xrandr does.