Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

     In our modern world, we're facing a significant issue with too much electronic waste. Consider all the gadgets we use every day, like phones, computers, and kitchen appliances. When they're no longer useful, they often end up as trash.

     The problem is, these gadgets contain harmful substances like lead and mercury. When they're thrown away, they can leak into the environment and make things unhealthy for people and animals. Plus, getting rid of all this electronic waste adds to pollution and worsens global warming.To address this, we need to take a few steps. Companies should make gadgets that last longer and are easier to recycle. We should also try to buy fewer new gadgets and reuse what we have. And it's important to recycle old electronics properly instead of simply throwing them away.

   Everyone, from regular people to big companies and governments, needs to work together on this. By being more careful with our electronics and finding better ways to deal with old gadgets, we can make the world a cleaner and safer place for everyone.

The passage is mainly about_______?