​Trees are one of the most important things on Earth. It provides us with our food, clothing, and shelter. Medicines also come from some trees and plants. Trees absorb water through their leaves, thus making the air around us much cooler. Trees in urban may worsen the air quality by trapping pollutants at street level. Forest trees regulate the flow of water and keep our rivers and streams supplied with groundwater all year round. They also prevent excess water from flowing and flooding low-lying areas which destroy homes and areas. Which sentence conveys an opinion based on the text?

​They regulate the flow of water and keep our rivers and streams supplied with ground water all year round.

Trees in urban may worsen the air quality by trapping pollutants at street level.

​Trees can trap pollutants at street level.

​Trees clean air and give oxygen supply.​