Answer:
Framing
Explanation:
Framing is changing the way that people think about something. Even if the situation is the same, framing helps change attitudes about it.
When enrollment was a choice, employees had to choose to lower their take home pay in order to put it into the retirement fund. This would feel like a negative to the employees (even though they are saving for retirement, they don't want to lower their pay). By automatically enrolling people, employees didn't have to make that difficult choice. They could opt out if they wanted, but now there was no risk of "losing out" on take home pay.