You manage a Ruby on Rails application that lives on a cluster of EC2 instances. Your website occasionally experiences brief, strong, and entirely unpredictable spikes in traffic that overwhelm your EC2 instances' resources and freeze the application. As a result, you're losing recently submitted requests from end users. You use Auto Scaling to deploy additional resources to handle the load during spikes, but the new instances don't spin-up fast enough to prevent the existing application servers from freezing. Which of the following will provide the most cost-effective solution in preventing the loss of recently submitted requests?
A. Keep a large EC2 instance on standby.
B. Increase the size of your existing EC2 instances.
C. Ask AWS support to pre-warm the Elastic Load Balancer.
D. Use Amazon SQS to decouple the application components and keep the requests in queue until the extra Auto-Scaling instances are available."