A healthcare company uses Amazon Redshift for data analysis. During an annual security audit the company's security team determines that the environment is not using encryption at rest. The security team recommends that the company turn on encryption of private information as soon as possible.
Which solution meets these requirements with the LEAST operational overhead?

A. Use the ALTER TABLE command with the ENCODE option to update existing private information columns in the Amazon Redshift tables to use LZO encoding.
B. Export data from the existing Amazon Redshift duster to Amazon S3 by using the UNLOAD command with the ENCRYPTED option. Create a new Amazon Redshift cluster with encryption enabled. Load data into the new cluster by using the COPY command.
C. Create a manual snapshot of the existing Amazon Redshift cluster. Restore the snapshot into a new Amazon Redshift cluster with encryption enabled.
D. Modify the existing Amazon Redshift cluster to use AWS Key Management Service (AWS KMS) encryption.