SELECT COL_A, COL_B , COL_C , COL_D , COL_E , COL_F
  FROM TAB_A
 WHERE COL_A = 050
   AND COL_B = 13012345
   AND COL_C = 0
   AND COL_D = 0
   AND COL_D >= '07/23/2013 00:00:00'
 ORDER BY COL_E ASC;

select COL_C, count(*)
  FROM TAB_A --very not selective for 0, selective for the rest, also no histogram
 group by rollup(COL_C)
 order by 2 desc;

COL_C	COUNT(*)
-----	--------
		158382
0		86356
6955837	72
6230441	69
6595589	64
6800455	64
6896642	63
6523986	61
7011681	60
6706623	60
6878281	60
6644220	59
7015911	59

Create index GOOD_IDX on TAB_A(COL_B) compute statistics;

 BEGIN
  DBMS_STATS.GATHER_TABLE_STATS ( 
    ownname    => 'ANDREY'
,   tabname    => 'TAB_A'
,   method_opt => 'FOR COLUMNS COL_C'
);
END;
/

select histogram from dba_tab_columns where table_name='TAB_A' 
and column_name='COL_C' and owner=user;

HISTOGRAM
----------
HEIGHT BALANCED

/*+ NO_INDEX(TAB_A BAD_IDX) */