Which solution should the solutions architect recommend?

Explanations:

Amazon EBS Cold HDD (sc1) is designed for infrequent access and low-cost storage, but it does not provide sufficient IOPS for the application’s peak requirement of 3,000 IOPS. This option sacrifices performance for cost, making it unsuitable for the use case.

Amazon EBS General Purpose SSD (gp2) offers a good balance of price and performance, supporting up to 16,000 IOPS for volumes over 1 TB, which meets the application’s peak IOPS requirement. It is cost-effective for applications with moderate I/O needs and can handle the varying disk I/O without significant performance loss.

Amazon EBS Provisioned IOPS SSD (io1) provides high-performance storage with customizable IOPS, which would exceed the needs of this application and incur higher costs than necessary. While it meets the IOPS requirement, it is not cost-effective given that gp2 suffices for the performance needed.

Amazon EBS Throughput Optimized HDD (st1) is suitable for large, sequential I/O workloads and can handle high throughput but is not optimized for random I/O performance, which is needed for the application. It may not meet the 3,000 IOPS requirement, making it a poor choice for this scenario.