You have created a load balancer in AWS with EC2 Instances behind them. The ELB is serving web traffic to users on the Internet. The Web servers behind the ELB are stateful. Users begin to report intermittent connectivity issues when accessing the website. What can be done to ensure that the issue is resolved?

Answer options:

A.Ensure that the Security Group for the web servers is open on port 443.
B.Ensure that the Security Group for the web servers are open for 0.0.0.0/0
C.Enable sticky sessions at the target group level.
D.Enable connection draining.

Answer – C
Option A is invalid because there is no mention of SSL in the question.
Option B is invalid because you should not allow access from anywhere on the EC2 Instances.
Option D is invalid because connection draining will not solve the issue.
The AWS Documentation mentions the following.
Sticky sessions are a mechanism to route requests to the same target in a target group. This is useful for servers that maintain state information to provide a continuous experience to clients. To use sticky sessions, the clients must support cookies.
For more information on sticky sessions for the ELB, please refer to the below URL on Page# 45 - Point# 9
https://docs.aws.amazon.com/elasticloadbalancing/latest/application/elb-ag.pdf#load-balancer-target-groups