how to prevent Ubuntu to automatically insert the modules

[loody]

Dear all:
I try to trace gadet Mass storage driver in kernel, but each time I
insert g_storage_file.ko the usb-storage.ko
will be automatically inserted.

Is there any way to prevent Ubuntu automatically instert the modules?
(I roughly know there is a dependency of modules but I have no idea
where and how to turn it off)
appreciate your help,
miloody