How to extract mutually disjoint elements of a list of lists

Extract mutually disjoint elements of a list:

 I have a list of lists, for example:

my_list = {{1,2,9},{2,3,7},{5,6,9},{8,10,11}}

Result is :(Try this ) i got form web 

fn=Module[{ms = Subsets[#, {2, Length@#}]}, 
  Take[Reverse[Pick[ms, And @@ DisjointQ @@@ Subsets[#, {2}] & /@ ms]],
UpTo[1]]] &;

mylist = {{1, 2, 9}, {2, 3, 7}, {5, 6, 9}, {8, 10, 11}}
fn@mylist

my_list = {{1,2,9},{2,3,7},{5,6,9},{8,10,11}}