How can the user add the sixth EC2 instance to ELB?

A user has launched five instances with ELB. How can the user add the sixth EC2 instance to ELB?

A.
The user can add the sixth instance on the fly.

B.
The user must stop the ELB and add the sixth instance.

C.
The user can add the instance and change the ELB config file.

D.
The ELB can only have a maximum of five instances.

Explanation:
Elastic Load Balancing automatically distributes incoming traffic across multiple EC2 instances. You create a load
balancer and register instances with the load balancer in one or more Availability Zones. The load balancer serves as a
single point of contact for clients. This enables you to increase the availability of your application. You can add and
remove EC2 instances from your load balancer as your needs change, without disrupting the overall flow of information.
http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/SvcIntro.html