You had set up an internal HTTP(S) Elastic Load Balancer to route requests to two EC2 instances inside a private VPC. However, one of the target EC2 instance is showing Unhealthy status. Which of the following options could not be a reason for this?
A. Port 80/443 is not allowed on EC2 instance’s Security Group from the load balancer.
B. An EC2 instance is in different availability zones than load balancer.
C. The ping path does not exist on the EC2 instance.
D. The target did not return a successful response code
