Explanation:
Box 1: Share1 only
Azure Backup policies can only back up an Azure VM, SQL in an Azure VM or File Share. As such the answer to the first part should be Share1 only.
Box 2: 99 years
With the latest update to Azure Backup, customers can retain their data for up to 99 years in Azure.
Note: A backup policy defines a matrix of when the data snapshots are taken, and how long those snapshots are retained.
The backup policy interface looks like this:

References: https://docs.microsoft.com/en-us/azure/backup/backup-azure-vms-first-look- arm#defining-a-backup-policy
https://blogs.microsoft.com/firehose/2015/02/16/february-update-to-azure-backup-includes-data- retention-up-to-99-years-offline-backup-and-more/