Exam 1z0-997-20 topic 1 question 15 discussion

I don't think it's necessarily wrong but is it necessary to do a volume group with only one volume in this case? I lean towards D since I see that in the docs 'Before creating a backup, you should ensure that the data is consistent: Sync the file system, unmount the file system if possible, and save your application data. Only the data on the disk will be backed up.' (https://docs.cloud.oracle.com/en-us/iaas/Content/Block/Concepts/blockvolumebackups.htm)

B is not correct because the application is not resilient with crash-consistent backups which you do online. From documentation. https://docs.oracle.com/en-us/iaas/Content/Block/Concepts/bootvolumebackups.htm Making a boot volume backup while an instance is running creates a crash-consistent backup, meaning the data is in the identical state it was in at the time the backup was made. This is the same state it would be in the case of a loss of power or hard crash. In most cases, you can restore a boot volume backup and use it to create an instance. Alternatively you can attach it to an instance as a data volume to repair it or recover data, see Attaching a Volume. To ensure a bootable image, you should create a custom image from your instance. For information about creating custom images, see Managing Custom Images.