Which option will provide (he most scalable solution for communicating between the application and SOS?

You have been asked to leverage Amazon VPC BC2 and SOS to implement an application that submits and receives millions of messages per second to a message queue. You want to ensure your application has sufficient bandwidth between your EC2 instances and SQS
Which option will provide (he most scalable solution for communicating between the application and SOS?
A. Ensure the application instances are properly configured with an Elastic Load Balancer
B. Ensure the application instances are launched in private subnets with the EBS-optimized option enabled
C. Ensure the application instances are launched in public subnets with the associate-public-IP-address=true option enabled
D. Launch application instances in private subnets with an Auto Scaling group and Auto Scaling triggers configured to watch the SOS queue size