Which kind of Amazon EBS volume should an Administrator choose for this solution?

Explanations:

Cloud HDD is not a valid Amazon EBS volume type. Instead, Amazon offers specific HDD options such as Throughput Optimized HDD and Cold HDD, but Cloud HDD is not one of them.

General Purpose SSD (gp2 or gp3) provides a balance of price and performance for a variety of workloads, but it is not specifically designed for sustained IOPS performance. It may not consistently deliver the high IOPS required for I/O-intensive applications.

Provisioned IOPS SSD (io1 or io2) is designed for applications that require high, consistent performance and sustained IOPS. This volume type allows you to provision up to 64,000 IOPS per volume, making it ideal for databases and other performance-sensitive applications.

Throughput Optimized HDD (st1) is designed for high-throughput workloads rather than IOPS performance. While it offers good performance for sequential I/O operations, it is not suited for the sustained random IOPS performance needed by databases.