You have an EC2 Instance in a private subnet that needs to access the KMS service privately within the AWS network. Which of the following methods can help to fulfill this requirement, keeping security in perspective?

Answer options:

A.Use a VPC endpoint.
B.Attach an Internet gateway to the subnet.
C.Attach a VPN connection to the VPC.D.Use VPC Peering.

Answer: A
Option A is CORRECT because when you use the VPC endpoint, communication between your VPC (EC2 within that) and AWS KMS is conducted entirely within the AWS network.
Option B is incorrect because the requirement is that the EC2 instance can reach KMS within the AWS Network, whereas Internet Gateway is used for EC2 machines to reach the Internet on a public network.
Option C is incorrect because AWS VPN is used for connecting on-premises environments and AWS and does not work within AWS services such as EC2 and KMS.
Option D is incorrect because VPC Peering is used for communication between several VPCs and would not help EC2 to communicate with KMS within the AWS network.
For more information on accessing KMS via an endpoint, please visit the following URL:
https://docs.aws.amazon.com/kms/latest/developerguide/kms-vpc-endpoint.html