Briefing Amazon Knowledge

What could be the cause of this?

You work for a construction company that has their production environment in AWS. The production
environment consists of 3 identical web servers that are launched from a standard Amazon linux AMI using
Auto Scaling. The web servers are launched in to the same public subnet and belong to the same security
group. They also sit behind the same ELB. You decide to do some test and dev and you launch a 4th EC2
instance in to the same subnet and same security group. Annoyingly your 4th instance does not appear to have
internet connectivity. What could be the cause of this?

A.
You need to update your routing table so as to provide a route out for this instance.

B.
Assign an elastic IP address to the fourth instance.

C.
You have not configured a NAT in the public subnet.

D.
You have not configured a routable IP address in the host OS of the fourth instance.