tunnelling a scp connection over multiple host

[RJ45 <rj45@slacknet.com>]

hello,
this is my configuration.
     
         ssh            ssh 
HOST A -------> HOST B -------->HOST C

if I connct from host A to host B and then from host B to host C
using SSH I would like to being able to forward an sc pconnection the same
way is done with X11, and with X11 I can forward it automaticcaly so that
applications launched on host C are forwarded to Host A.

Is it possible to do the same ? Can I make a scp to host C passing from
Host B but copying my files on Host A ?
Host B is my ssh gateway. People logins on Host B and the from host B they
login to their host C. They are able to work also with X11 but they cannot
use scp from host A to copy files which are on Host C And I Am not able to
solve this problem.
I do not want to use the gateway host B as a temporary download host for
scp connection, I would like scp to be forwarded to host A in some way.
I don't know if it is possible.

thank you

Rick