Answer: B. Increased surface runoff has increased water pollutants.
Explanation:
Trees provide a very valuable service in limiting the effects of surface runoff such as the reduction of soil erosion on account of trees holding the soil together with their roots. Their presence also reduces the actual surface runoff because they impede the path of the water.
With deforestation getting rid of trees, they would be unable to anchor the soil and reduce the movement of water which means that surface runoff will increase.
