Which configuration should a solutions architect recommend?
Use one SQS FIFO queue. Assign a higher priority to the paid photos so they are processed first.
Use two SQS FIFO queues: one for paid and one for free. Set the free queue to use short polling and the paid queue to use long polling.
Use two SQS standard queues: one for paid and one for free. Configure Amazon EC2 instances to prioritize polling for the paid queue over the free queue.
Use one SQS standard queue. Set the visibility timeout of the paid photos to zero. Configure Amazon EC2 instances to prioritize visibility settings so paid photos are processed first.
Explanations:
SQS FIFO queues do not support prioritizing messages within the same queue, so paid photos cannot be prioritized.
Polling settings (short and long) do not affect message priority, and both types of users would experience delays.
Separate SQS standard queues allow prioritizing the paid queue over the free queue, enabling preferred processing.
Visibility timeout controls message reprocessing, not priority, so it cannot ensure paid photos are processed first.
I map out that the answer is:
Use two SQS standard queues: one for paid and one for free. Configure Amazon EC2 instances to prioritize polling for the paid queue over the free queue.