At least how many weighings of a balanced scale are needed to order four stones with distinct weights from the lightest to the heaviest?<spanclass=′latex−bold′>(A)</span>4<spanclass=′latex−bold′>(B)</span>5<spanclass=′latex−bold′>(C)</span>6<spanclass=′latex−bold′>(D)</span>7<spanclass=′latex−bold′>(E)</span>8