What should you do?

You have an Azure subscription that contains 100 virtual machines. You regularly create and delete virtual machines. You need to identify unattached disks that can be deleted.

What should you do?
A . From Microsoft Azure Storage Explorer, view the Account Management properties.
B . From Azure Cost Management, create a Cost Management report.
C . From the Azure portal, configure the Advisor recommendations.
D . From Azure Cost Management, open the Optimizer tab and create a report.

Answer: D

Explanation:

You can find unused disks in the Azure Storage Explorer console. Once you drill down to the Blob containers under a storage account, you can see the lease state of the residing VHD (the lease state determines if the VHD is being used by any resource) and the VM to which it is leased out. If you find that the lease state and the VM fields are blank, it means that the VHD in question is unused.

Note: The ManagedBy property stores the Id of the VM to which Managed Disk is attached to. If the ManagedBy property is $null then it means that the Managed Disk is not attached to a VM

Reference:

https://cloud.netapp.com/blog/reduce-azure-storage-costs