An application uses a Lambda function with an SQS queue named high priority queue as an event source. A second SQS queue, low priority queue, is being added. The Lambda function must always read up to 10 concurrent messages from high priority queue before consuming from low priority queue, and the Lambda must never exceed 100 concurrent invocations. Which configuration meets these requirements?

The correct option is to set the event source mapping maximum concurrency. This directly controls how many concurrent Lambda invocations can process messages from each SQS queue. By setting the high priority queue's maximum concurrency to 10, it ensures that up to 10 messages are processed concurrently from this queue. Setting the low priority queue's maximum concurrency to 90 allows it to use the remaining capacity (100 total - 10 for high priority = 90) once the high priority queue has consumed its share. The Lambda function will prioritize the high priority queue up to its limit before the low priority queue receives significant processing. Incorrect options: Batch size defines how many messages are processed in a single invocation, not the number of concurrent invocations. Delivery delay affects when messages become visible in the queue, not the concurrency of Lambda processing. Batch window defines the maximum time Lambda waits to gather a batch of messages, not the concurrency.