Which file defines the fields for each object used in the file objects.C (color, num/string, default value…)?

Which file defines the fields for each object used in the file objects.C (color, num/string,
default value…)?

A.
$FWDIR/conf/table.C

B.
$FWDIR/conf/classes.C

C.
$FWDIR/conf/scheam.C

D.
$FWDIR/conf/fields.C