Your organization had set up Auto Scaling for an EC2 instance. They intend to launch one additional new instance with same configuration automatically when the workload increases and shut it down automatically when the workload is back to normal. However, they have applied operating system patches to the main instance for security reasons and would like this to be reflected when the Auto Scaling group launches a new EC2 instance. What actions would you take in this scenario?

Answer options:

A.Auto Scaling group will launch new EC2 instance from the main instance latest snapshot. New instance will have updated patches.
B.Create an image out of main EC2 instance and update Auto Scaling group configuration with new image AMI ID.C.Create an image out of main EC2 instance and update Launch Configuration with new image AMI ID.D.Create an image out of main EC2 instance, create a new Launch Configuration with new image AMI ID, update Auto Scaling group with new Launch Configuration ID

Answer: D
Option A is not correct.
Auto Scaling group launches new instances based on the configuration defined in Launch Configuration. AMI ID is one of the configuration parameter which defines the type of instance to be launched when auto-scaling logic is executed.
AMI ID is set during the creation of the launch configuration and cannot be modified.
So, the auto-scaling group will not launch a new instance based on the latest image of the main instance.
Option B is not correct.
AMI ID is a configuration on Launch Configuration, not Auto Scaling Group.
Option C is not correct and Option D is correct.
 
https://docs.aws.amazon.com/autoscaling/ec2/userguide/change-launch-config.html