Since it is in the directory data/, You need to do:
file path is '../../data/file.json'
$.getJSON('../../data/file.json', function(data) {
alert(data);
});
Pure JS:
var request = new XMLHttpRequest();
request.open("GET", "../../data/file.json", false);
request.send(null)
var my_JSON_object = JSON.parse(request.responseText);
alert (my_JSON_object.result[0]);