For which reason would you modify the VHSBCONF configuration file?

A.
to set up multiple VHS environments or add a user-written filter program

B.
to change the location of the VHS primary log file or add a user-written filter program

C.
to change the location of the VHS primary log file or set up multiple VHS environments

D.
to add a user-written filter program or configure additional error messages to be monitored