What is the origin of the term ‘The Whole Nine Yards’?

This phrase origins has several interpretations. Some popular ones are as follows: nine yards probably refers to the amount of cloth / material needed to make a wedding dress or bridal train, a man’s three piece suit or a burial shroud. Also, the term, perhaps, comes from from World War II pilots who wanted to be sure that they were fully loaded with ammunition before take-off. The ammunition belts were normally 27 ft or 9 yards. Alternatively, the term comes from the capacity of ready-mix concrete trucks which were normally 9 cubic yards the whole nine yards referred to a fully loaded concrete truck.