A.CREATE INDEXfl_idx ON employees(first_name last_name)
B.CREATE INDEXfl_idx ON employees(first_name),employees(last_name)
C.CREATE INDEXfl_idx ON employees(first_name,last_name)
D.CREATE INDEXfl_idx ON employees(first_name);CREATE INDEXfl_idx ON employees(last_name)