Final answer:
Only one Delete lock can be applied to a single Azure resource, which protects the resource from accidental deletion regardless of user permissions. Delete locks can also be placed on resource groups or at the subscription level.
Step-by-step explanation:
The number of Delete locks that can be applied to a single Azure resource is only one. Azure allows for various types of management locks to prevent accidental deletion or modification of resources, but you can only have one Delete lock per resource. This type of lock ensures that the resource cannot be accidentally deleted without first removing the lock.
It's also important to note that the Delete lock can be applied at different levels including individual resources, resource groups, and even at the subscription level. Once applied, the Delete lock overrides any permissions the user might have, meaning that even users with the right to delete a resource will be unable to do so until the Delete lock is removed.