What must be configured on the FWSM to forward traffic to a filtering server?

What must be configured on the FWSM to forward traffic to a filtering server?

A.
the filtering server as an authentication provider (aaa-server)

B.
all web traffic so that it is directed only to the filtering server (access-list)

C.
all HTTP requests so that they are redirected to the filtering server (fixup protocol)

D.
all HTTP requests so that they are sent to the filtering server (url-server)