Check if the predicate (second argument) is truthy on all elements of a collection (first argument). Remember, you can access object properties through either dot notation or [] notation.

everything-be-true.js

function truthCheck(collection, pre) {
  // Is everyone being true?
  //set a variable to count the truthies
  var truthy = 0;
  //loop over the array and test for true
  //if it's true add one to truth
  for(var i = 0; i<collection.length; i++){
    if(collection[i][pre]){
      truthy ++;
    }
  }
  //check if everything is true by comparing truthy to the array length.
  return (truthy === collection.length);
}

truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex");