Explanation
A terraform list is a sequence of values identified by consecutive whole numbers starting with zero. https://www.terraform.io/docs/configuration/types.html#structural-types

Terraform is able to import existing infrastructure. This allows us take resources we've created by some other means (i.e. via console) and bring it under Terraform management.
This is a great way to slowly transition infrastructure to Terraform.
The terraform import command is used to import existing infrastructure.
To import a resource, first write a resource block for it in our configuration, establishing the name by which it will be known to Terraform.
Example:
resource "aws_instance" "import_example" {
# ...instance configuration...
}
Now terraform import can be run to attach an existing instance to this resource configuration.
$ terraform import aws_instance.import_example i-03efafa258104165f
aws_instance.import_example: Importing from ID "i-03efafa258104165f"...
aws_instance.import_example: Import complete!
Imported aws_instance (ID: i-03efafa258104165f)
aws_instance.import_example: Refreshing state... (ID: i-03efafa258104165f) Import successful!
The resources that were imported are shown above. These resources are now in your Terraform state and will henceforth be managed by Terraform.
This command locates the AWS instance with ID i-03efafa258104165f (which has been created outside Terraform) and attaches its existing settings, as described by the EC2 API, to the name aws_instance.import_example in the Terraform state.

Explanation
You may see this question in actual exam. Please remember : Terraform does not require GO language to be installed as a prerequisite and it does not require a Windows Server as well.

Explanation
Terraform is built on a plugin-based architecture. All providers and provisioners that are used in Terraform configurations are plugins, even the core types such as AWS and Heroku. Users of Terraform are able to write new plugins in order to support new functionality in Terraform.