Your startup wants to implement an order fulfillment process for selling a personalized gadget
that needs an average of 3-4 days to produce with some orders taking up to 6 months.
You expect 10 orders per day on your first day, 1000 orders per day after 6 months and 10,000
orders after 12 months. Orders coming in are checked for consistency, then dispatched to your
manufacturing plant for production, quality control, packaging, shipment and payment processing.
If the product does not meet the quality standards at any stage of the process, employees may
force the process to repeat a step. Customers are notified via email about order status and any
critical issues with their orders such as payment failure.
Your base architecture includes AWS Elastic Beanstalk for your website with an RDS MySQL
instance for customer data and orders.
How can you implement the order fulfillment process while making sure that the emails are
delivered reliably?

A.
Add a business process management application to your Elastic Beanstalk app servers and reuse the RDS database for tracking order status.
Use one of the Elastic Beanstalk instances to send emails to customers.

B.
Use SWF with an Auto Scaling group of activity workers and a decider instance in another Auto
Scaling group with min/max=1.
Use SES to send emails to customers.

C.
Use an SQS queue to manage all process tasks. Use an Auto Scaling group of EC2 instances
that poll the tasks and execute them.
Use SES to send emails to customers.

D.
Use SWF with an Auto Scaling group of activity workers and a decider instance in another Auto
Scaling group with min/max=1.
Use the decider instance to send emails to customers.

Explanation:
http://media.amazonwebservices.com/architecturecenter/AWS_ac_ra_ecommerce_checkout_13.
pdf