A user has configured ELB with a TCP listener at ELB as well as on the back-end instances. The user wants to enable a proxy protocol to capture the source and destination IP information in the header. Which of the below mentioned statements helps the user understand a proxy protocol with TCP configuration?

If the end user is requesting behind a proxy server then the user should not enable a proxy protocol on ELB 

ELB does not support a proxy protocol when it is listening on both the load balancer and the back- end instances 

Whether the end user is requesting from a proxy server or directly, it does not make a difference for the proxy protocol 

If the end user is requesting behind the proxy, then the user should add the “isproxy” flag to the ELB Configuration