밑줄 친 this 가 가리키는 것은?

1.

People spend money to buy unnecessary things every day. It begins with a little snack after school or some gum while waiting for the bus. Then it is an attractive toy dog that you might misplace or throw away a week later. Or it is a shirt you might rarely wear. Perhaps it is a comic book you will be through within an hour. Before you know it, your room is full of things you do not need. Nevertheless, you're not happy. And your wallet is empty! This is a common story in modern society. But we can cut down on our spending. We may even ask, "Can we go just this without purchasing anything?

① money② a little snack

③ one day④ our spending

⑤ a comic book

2.

Several years ago, a small group of people in Vancouver, Canada, started to put this idea into action. They bought nothing for one whole day, and they encouraged other people to do the same. They believed the people of this planet should think about the dangers of this.

① spending money

② buying a comic book

③ cutting our spending

④ mindless shopping

⑤ putting this idea into action