Rany is conducting research to support his claim that happy people are more productive in their jobs than unhappy people, and he
finds this text in a reliable source. (1) There are many different factors that affect workplace productivity. (2) Research tells us that an employee’s level of happiness can impact how he or she performs. (3) In fact, one study showed that people who identified as being happy are twelve percent more productive than their colleagues. (4) An employee’s interest level in a given subject or task and ability level are other factors that play a role in how that person does his or her job.
Which sentence contains a detail that best supports Rany’s claim?