Choose the correct option.
1. People must stop destroying forests so / because we need forests for oxygen.
2. Temperatures are increasing because / so there is global warming.
3. Cars emit exhaust fumes, because / so they make the air dirty and cause air pollution.
4. We must recycle plastic and glass, so / because we can reduce our waste and reuse them.
5. We should use renewable energy like solar energy so / because it is not harmful to the Earth.​