Your company network has two physical locations configured in a geo-clustered environment. You create a
Blob storage account in Azure that contains all the data associated with your company.
You need to ensure that the data remains available in the event of a site outage.
Which storage option should you enable?

A.
Locally redundant storage

B.
Geo-redundant storage

C.
Zone-redundant storage

D.
Read-only geo-redundant storage

Explanation:
Introducing Read-only Access to Geo Redundant Storage (RA-GRS):
RA-GRS allows you to have higher read availability for your storage account by providing “read only”
access to the data replicated to the secondary location. Once you enable this feature, the secondary
location may be used to achieve higher availability in the event the data is not available in the primary
region. This is an “opt-in” feature which requires the storage account be geo-replicated.

Windows Azure Storage Redundancy Options and Read Access Geo Redundant Storage