jQuery.extend is not a copy for Object!!!

jQuery.extend is not a copy for Object!!!

  2.       var A = {
  3.       info:{
  4.             name:'a'
  5.       }
  6.       };
  7.       var B = extend({}, A);
  8.       B.info.name='b';
  9.       console.log(A); // A.info.name  is change to b