Answer: D. All of the above
Explanation: The three options listed could explain why the productivity of labor increased with a reduction in the quantity of labor hired. The law of diminishing returns states that as more and more inputs of production are added, a time comes in when additional inputs causes no corresponding increase in productivity. At points like this a reduction in the input added would restore productivity.
Reducing the amount of labor obviously is a labour saving technical change. Changes in organizational innovation can also result in changes in productivity.
