A company has a Redshift Cluster defined in AWS. The IT Operations team has ensured that both automated and manual snapshots are in place. Since the cluster will be run for a couple of years, Reserved Instances have been purchased. There has been a recent concern about the cost being incurred by the cluster. Which step should be carried out to minimize the costs being incurred by the cluster?

Answer options:

A.Delete the manual snapshots.
B.Set the retention period of the automated snapshots to 35 days.
C.Choose to use Spot Instances instead of Reserved Instances.
D.Choose to use Instance store volumes to store the cluster data.

Correct Answer - A
AWS Documentation mentions the following.
Regardless of whether you enable automated snapshots, you can take a manual snapshot whenever you want at any time. By default, manual snapshots are retained indefinitely, even after you delete your cluster. You can specify the retention period when you create a manual snapshot or change the retention period by modifying the snapshot.
To reduce cost, we can delete the manual snapshots that are taken, if any.
Refer link: https://aws.amazon.com/redshift/pricing/
Automated snapshots are automatically deleted within the period of 1(Least) to 35(Max) days (Based on the retention period settings). So we have to take care of the Manual snapshots instead of Automated snapshots. Amazon Redshift never deletes Manual snapshots automatically, like how it does for Automatic Snapshots.
Option B is incorrect because the Automated snapshots are automatically deleted within the period of 1(Least) to 35(Max) days. This will NOT have any impact on the cost
Option C is incorrect because SPOT instances are not a good fit for snapshot and the question does not mention one of these.
Option D is incorrect because instance store volumes are volatile and therefore is NOT a good fit for the snapshot.
For more information on working with Snapshots, please visit the following URL-
https://docs.aws.amazon.com/redshift/latest/mgmt/working-with-snapshots.html