You Work for a Startup That Has Developed a New

You work for a startup that has developed a new photo-sharing application for mobile devices. Over recent months, your application has increased in popularity; this has resulted in a decrease in the performance of the application clue to the increased load. Your application has a two-tier architecture that is composed of an Auto Scaling PHP application tier and a MySQL RDS instance initially deployed with AWS CloudFormation. Your Auto Scaling group has a min value of 4 and a max value of 8. The desired capacity is now at 8 because of the high CPU utilization of the instances. After some analysis, you are confident that the performance issues stem from a constraint in CPU capacity, although memory utilization remains low. You therefore decide to move from the general-purpose M3 instances to the compute-optimized C3 instances. How would you deploy this change while minimizing any interruption to your end users?

A) Sign into the AWS Management Console, copy the old launch configuration, and create a new launch configuration that specifies the C3 instances. Update the Auto Scaling group with the new launch configuration. Auto Scaling will then update the instance type of all running instances.
B) Sign into the AWS Management Console, and update the existing launch configuration with the new C3 instance type. Add an UpdatePolicy attribute to your Auto Scaling group that specifies AutoScalingRollingUpdate.
C) Update the launch configuration specified in the AWS CloudFormation template with the new C3 instance type. Run a stack update with the new template. Auto Scaling will then update the instances with the new instance type.
D) Update the launch configuration specified in the AWS CloudFormation template with the new C3 instance type. Also add an UpdatePolicy attribute to your Auto Scaling group that specifies AutoScalingRollingUpdate. Run a stack update with the new template.