To establish a BGP session between two BGP speakers, what will be the first BGP message sent by each BGP speaker after the transport protocol connection is established?

To establish a BGP session between two BGP speakers, what will be the first BGP message sent by each BGP speaker after the transport protocol connection is established?

A.
hello

B.
query

C.
open

D.
sync

E.
update

F.
notification