A company runs an application on a large fleet of Amazon EC2 instances. The application reads and write entries into an Amazon DynamoDB table. The size of the DynamoDB table continuously grows, but the application needs only data from the last 30 days. The company needs a solution that minimizes cost and development effort.

Which solution meets these requirements?

A. Use an AWS CloudFormation template to deploy the complete solution. Redeploy the CloudFormation stack every 30 days, and delete the original stack.

B. Use an EC2 instance that runs a monitoring application from AWS Marketplace. Configure the monitoring application to use Amazon DynamoDB Streams to store the timestamp when a new item is created in the table. Use a script that runs on the EC2 instance to delete items that have a timestamp that is older than 30 days.

C. Configure Amazon DynamoDB Streams to invoke an AWS Lambda function when a new item is created in the table. Configure the Lambda function to delete items in the table that are older than 30 days.

D. Extend the application to add an attribute that has a value of the current timestamp plus 30 days to each new item that is created in the table. Configure DynamoDB to use the attribute as the TTL attribute.

Amazon DynamoDB Time to Live (TTL) allows you to define a per-item timestamp to determine when an item is no longer needed. Shortly after the date and time of the specified timestamp, DynamoDB deletes the item from your table without consuming any write throughput. TTL is provided at no extra cost as a means to reduce stored data volumes by retaining only the items that remain current for your workload’s needs. Archive expired items to an Amazon S3 data lake via Amazon DynamoDB Streams and AWS Lambda. Retain sensitive data for a certain amount of time according to contractual or regulatory obligations. https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/TTL.html

A company has deployed a database in Amazon RDS for MySQL. Due to increased transactions, the database support team is reporting slow reads against the DB instance and recommends adding a read replica.

Which combination of actions should a solutions architect take before implementing this change? (Choose two.)

A. Enable binlog replication on the RDS primary node.

B. Choose a failover priority for the source DB instance.

C. Allow long-running transactions to complete on the source DB instance.

D. Create a global table and specify the AWS Regions where the table will be available.

E. Enable automatic backups on the source instance by setting the backup retention period to a value other than 0.

"An active, long-running transaction can slow the process of creating the read replica. We recommend that you wait for long-running transactions to complete before creating a read replica. If you create multiple read replicas in parallel from the same source DB instance, Amazon RDS takes only one snapshot at the start of the first create action. When creating a read replica, there are a few things to consider. First, you must enable automatic backups on the source DB instance by setting the backup retention period to a value other than 0. This requirement also applies to a read replica that is the source DB instance for another read replica" https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html

A company needs to keep user transaction data in an Amazon DynamoDB table. The company must retain the data for 7 years.