Сопоставление предложений:
- 1 - c: One way to improve air quality is to ban cars from city centres. The result would be fewer cars on the roads and consequently fewer harmful gases would be released.
- 2 - a: One way to have less smog over cities is to remove factories from cities. The result would be cleaner air to breathe.
- 3 - b: One way to have litter disposed of properly is to deal with the litter problem-more rubbish bins in public places. The result would be properly-cleaner streets.
Ответ: 1-с, 2-а, 3-b