Assign a group or sequential Elastic IP address to the instances
Launch the instances in a Placement Group
Launch the instances in the Amazon virtual Private Cloud (VPC).
Use standard EC2 instances since each instance gets a private Domain Name Service (DNS) already
Launch the Instance from a private Amazon Machine image (Mil)
Explanations:
Elastic IP addresses are public IP addresses that can be assigned to EC2 instances. They are not used for assigning private IP addresses. Private IP addresses are assigned automatically by AWS when launching instances in a VPC.
Placement Groups are used to influence the placement of instances for performance purposes, such as low-latency networking. They do not affect the assignment of private IP addresses.
Launching instances in an Amazon VPC allows you to assign specific private IP addresses within the subnet. This is the only option that directly supports assigning predetermined private IP addresses.
Standard EC2 instances automatically receive private DNS names, but this does not allow for predetermined private IP address assignments. They still get dynamically assigned private IPs unless specified otherwise in a VPC.
A private Amazon Machine Image (AMI) does not relate to the assignment of private IP addresses. The private IP address assignment is based on the VPC subnet configuration rather than the type of AMI used.
I plot that the answer is:
Launch the instances in the Amazon virtual Private Cloud (VPC).