Siero and Colleagues (1996)introduced an Intervention to Reduce Energy Consumption

Siero and colleagues (1996) introduced an intervention to reduce energy consumption in different units of Dutch factories.Which of the following aspects of their intervention had the greatest (positive) impact on energy use?

A) raising prices for those that did not reduce energy consumption
B) placing announcements in company magazines
C) offering cash incentives for energy saving measures
D) providing feedback on other units' consumption
E) providing weekly feedback on a unit's consumption