Which storage solution should the solutions architect use?

Explanations:

While Amazon Elastic Block Store (EBS) provides durable block storage, it is typically limited to a single EC2 instance and may not meet the high throughput requirements across multiple instances effectively.

Amazon EC2 instance store offers high throughput and low latency, making it suitable for workloads that require millions of transactions per second. However, it is ephemeral and data is lost if the instance fails, which contradicts the need for data persistence across instances.

Amazon Elastic File System (EFS) is designed for scalable file storage but does not provide the low latency and high throughput required for block storage in a distributed database scenario.

Amazon S3 is an object storage service and is not suitable for use as block storage for databases requiring high transaction rates and low latency. It is designed for durability and scalability but not for block-level operations.