Based on the code you gave to create the 3 tables and insert the test data, the following returned the exact 5 records you wanted:

select TableA.*, TableB.*, TableC.*;
  from TableA ;
  Left Join TableB ;
  on TableA.Ident = TableB.Ident ;
  and TableA.FKey = TableB.FKey ;
  Left Join TableC ;
  on TableA.Ident = TableC.Ident ;
  having (isnull(TableB.FiltB) or TableB.FiltB = 1) ;
  and (isnull(TableC.FiltC) or TableC.FiltC = 1)