javascript - Extract fixed values from json object -

i have json object :

[  [     "a",     "1"  ],  [     "b",     "2"  ],  [     "c",     "3"  ],  [     "d",     "4"  ],  [     "e",     "5"  ],  [     "f",     "6"  ] ] 

i want retrieve key/value pair except a, d . there way in javascript ?

this doesn't json object, more 2-dimensional array.

here how can retrieve 2-dimensional array excluding "a" , "d" elements:

<script type="text/javascript">     var = [         [             "a",             "1"         ],         [             "b",             "2"         ],         [             "c",             "3"         ],         [             "d",             "4"         ],         [             "e",             "5"         ],         [             "f",             "6"         ]     ];     var b = [];     (var i=0; i<a.length; i++)         if (a[i][0] != "a" && a[i][0] != "d")             b.push(a[i]); </script>