A company hosts a microservices application that uses Amazon API Gateway, AWS Lambda, Amazon Simple Queue Service (Amazon SOS), and Amazon DynamoDB, One of the Lambda functions adds messages to an SOS FIFO queue.

When a developer checks the application logs, the developer finds a few duplicated items in a DynamoDB table. The items were inserted by another polling function that processes messages from the queue.

What is the MOST likely cause of this issue?

A company's ecommerce website is experiencing massive traffic spikes, which are causing performance problems in the company database. Users are reporting that accessing the website takes a long time

A developer wants to implement a caching layer using Amazon ElastiCache. The website is required to be responsive no matter which product a user views, and the updates to product information and prices must be strongly consistent

An application needs to encrypt data that is written to Amazon S3 where the keys are managed in an on-premises data center and the encryption is handled by S3. Which type of encryption should be used?