Jonathan, a front desk executive at Read Books Inc., handled $40$ customer calls per day. He was then sent to a training program last month to improve his communication skills, which cost the organization $$500.$ This month, Read Books observes that his growth is positive and substantial and that he is able to handle $60$ customer calls per day. His productivity has increased by $$700.$ This scenario most likely exemplifies

The heroix theory

The constructionist approach

Action learning

Return on investment