Correct answer - "Use the header X-Forwarded-For" : The X-Forwarded-For request header helps you
identify the IP address of a client when you use an HTTP or HTTPS load balancer. Because load
balancers intercept traffic between clients and servers, your server access logs contain only
the IP address of the load balancer. To see the IP address of the client, use the
X-Forwarded-For request header.
Incorrect:
"We should change the client application to send their IP as part of the payloads" - You have no
control of changing the IP address from the client side
"Use the header X-Forwarded-IP" - This header is used to retrieve the IP address from a user
connecting to an email server
"Change the security groups rules" - Security group rules filter traffic coming into and out of
an EC2 instance