EBS

EBS is attached to the EC2/POD EFS is good choice it is expandable ..When we set flag = y good where we are getting market data etc

EC2

a stopped instance that had been using a nonpersistent public IP address will most likely be assigned a different address when it's restarted. If you need a predictable IP address that can survive restarts, allocate an elastic IP address and associate it with your instance

VPC Router & IGW

A VPC can have no IG, which makes it inaccessable to the internet or it can have one IG.Those are the only 2 choices. An internet GW can be created and not attached to any VPC but it can be only attached to one VPC.

AWS KMS

AWS S3

Object Versioning

When versioning is disabled, id is set to null.