Google ACE Practice Question: A billing report shows a Compute Engine VM has…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Delete the VM to avoid all compute charges

  Why it's wrong here

  Deleting the VM permanently removes the instance, and by default the attached boot disk is deleted along with it, risking total data loss unless you explicitly detached the disk first. Even if you preserve the disk, you lose the instance's OS state, assigned internal/external IPs, metadata, and attached non-boot disk associations, requiring a full reconfiguration later. Stopping the VM achieves the same cost savings (no compute charges) without any of these destructive, irreversible consequences.

• ✓

  Stop (shut down) the VM — compute charges stop but disk storage charges continue

  Why this is correct

  Stopping (shutting down) a VM transitions it to the TERMINATED state, which immediately halts billing for vCPUs, memory, and other compute resources, though persistent disk storage, static IPs, and other resources continue to incur charges. All data on the boot and data disks remains intact, and the VM can be restarted with the same configuration at any time. This is the simplest and most cost-effective way to pause an unused VM without data loss, because it eliminates the only charges you can fully remove without destroying anything.

• ✗

  Snapshot the VM disk and delete the VM

  Why it's wrong here

  Snapshoting the disk and deleting the VM also stops compute charges, but it introduces unnecessary complexity and risk: you must restore from the snapshot to a new VM later, which recreates the disk but does not restore the exact original instance configuration (machine type, network tags, IP assignments, metadata). The snapshot itself incurs Cloud Storage costs, which can exceed the persistent disk cost during the idle period. Stopping the VM preserves the exact instance state and avoids snapshot restore time and configuration drift.

• ✗

  Set the VM to a smaller machine type to reduce costs

  Why it's wrong here

  Setting the VM to a smaller machine type reduces the per-hour compute rate, but the instance continues running and still accrues compute charges (for vCPUs and memory) at a lower, yet nonzero, cost. For a VM that is unused, stopping completely eliminates compute billing while preserving the machine configuration. Resizing also requires a restart and does not address the idle state; it only reduces the burn rate, not to zero.

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