Correct Answer: A

Explanation from Amazon documents:

Amazon RDS for Microsoft SQL Server supports two types of database snapshots: automated and manual. Automated snapshots are taken daily and are retained for a period of time that you specify, from 1 to 35 days. Manual snapshots are taken by you and are retained until you delete them.

To save a particular automated database snapshot for longer than the maximum number of days, the database administrator can create a manual copy of the snapshot. This can be done using the AWS Management Console, the AWS CLI, or the RDS API. The manual copy of the snapshot will be retained until it is deleted, regardless of the retention period of the automated snapshot. This solution is the most operationally efficient way to meet the requirements, because it does not require any additional steps or resources.

Therefore, option A is the correct solution to meet the requirements. Option B is not operationally efficient because it requires exporting the contents of the snapshot to an Amazon S3 bucket, which can be time-consuming and costly. Option C is not possible because the maximum retention period for automated snapshots is 35 days, not 45 days. Option D is not operationally efficient because it requires creating a native SQL Server backup and saving it to an Amazon S3 bucket, which can also be time-consuming and costly.

g%20scripts%20and%20cleanup%20jobs%2C%20you%20can%20use%20AWS%20Backup%20to%20create%20backup%20plans%20with%20schedules%20and%20retention%20policies%20for%20your%20DynamoDB%20tables.%20AWS%20Backup%20runs%20the%20backups%20and%20deletes%20them%20when%20they%20expire.%20For%20more%20information%2C%20see%20the%20AWS%20Backup%20Developer%20Guide.

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