Which of the below mentioned AWS services will help make a scalable software with the AWS infrastructure in this scenario?

A user has created photo editing software and hosted it on EC2. The software accepts requests from the user about the photo format and resolution and sends a message to S3 to enhance the picture accordingly.

Which of the below mentioned AWS services will help make a scalable software with the AWS infrastructure in this scenario?
A . AWS Simple Notification Service
B . AWS Simple Queue Service
C . AWS Elastic Transcoder
D . AWS Glacier

Answer: B

Explanation:

Amazon Simple Queue Service (SQS) is a fast, reliable, scalable, and fully managed message queuing service. SQS provides a simple and cost-effective way to decouple the components of an application. The user can configure SQS, which will decouple the call between the EC2 application and S3. Thus, the application does not keep waiting for S3 to provide the data.

Reference: http://aws.amazon.com/sqs/faqs/