You have an Azure Storage account named storage1 that contains a blob container named container1. You need to prevent new content added to container1 from being modified for one year. What should you configure?

To prevent new content in a blob container from being modified for a specific period, you should configure an immutability policy. Azure Blob Storage provides time-based retention policies that store data in a WORM (Write-Once, Read-Many) state. This policy makes the data non-erasable and non-modifiable for a user-specified interval, such as one year. This feature is configured for a container under its Access policy settings in the Azure portal, where you can add an "Immutable blob storage" policy.

A. the access tier: Access tiers (Hot, Cool, Cold, Archive) are used for storage cost optimization based on data access frequency and do not provide data immutability.
C. the Access control (IAM) settings: IAM roles control user and service principal permissions (who can do what), but they do not make the data itself inherently unchangeable for all users.
D. the access level: The access level (Private, Blob, or Container) configures the level of public, anonymous access to a container and its blobs, not modification rules for authenticated users.

1. Microsoft Learn

"Store business-critical blob data with immutable storage."

Reference: Under the "About immutable storage for blobs" section

it states

"Immutable storage for Azure Blob Storage enables users to store business-critical data objects in a WORM (Write

Once

Read

Many) state...blobs cannot be modified or deleted."

Reference: Under the "Time-based retention policies" section

it details

"When a time-based retention policy is applied to a container

all blobs in the container will stay in the non-erasable

non-modifiable state for the duration of the effective retention period."

2. Microsoft Learn

"Configure immutability policies for containers."

Reference: The "Configure a time-based retention policy" section provides a step-by-step guide. Step 4 explicitly states: "In the Azure portal

navigate to the Access policy settings page for the container." This confirms that the configuration is done via the access policy settings.