Which virt-install command creates a KVM virtual machine with a headless display and a 2GB RAM allocation, 20GB disk, and a CD-ROM OS image?

• A. virt-install --name testvm --ram 2048 --disk size=20 --os-variant=generic --graphics none --cdrom /path/to/os.iso
• B. virt-install --name testvm --ram 2048 --disk size=20 --os-variant=generic --graphics vnc --cdrom /path/to/os.iso
• C. virt-install --name testvm --ram 1024 --disk size=10 --os-variant=generic --graphics none --cdrom /path/to/os.iso
• D. virt-install --name testvm --ram 4096 --disk size=40 --os-variant=generic --graphics none --cdrom /path/to/os.iso

Answer: (A)

This question tests how to configure virt-install to run a VM headlessly with specific resources and an ISO install image. To get a headless VM, you need no graphical display, which is done with --graphics none. For the requested 2 GB of RAM, use --ram 2048 (RAM is in megabytes, so 2048 MB equals 2 GB). For a 20 GB disk, --disk size=20 sets the disk to 20 GB. And to boot from an OS image via CD-ROM, use --cdrom /path/to/os.iso. The combination that includes all of these exact settings is the command that uses --ram 2048, --disk size=20, --graphics none, and --cdrom /path/to/os.iso. The other options either allocate different RAM or disk sizes or enable a graphical display, so they don’t meet all the requirements.