urbanization is the answer
Reforestation is when you plant trees. Generally they do this in places that they have cut trees down. They do this to replace the trees they cut down. Therefore reforestation is a positive impact
Urbanization is basically making land into a city. This is negative because it is destroying habitats that were previously there and the traffic will cause air pollution in the area around it. There are other negative impacts of urbanization but I can't think of any more at the moment.
Terrace farming is...oof Idk how to explain it... it's basically where they cut steps into hills and farm on them. I'll link a picture below so you know what it looks like. This is a good way to use all the land possible. It's also one of the best ways to decrease erosion. This is positive use of the land.
btw you put reforestation twice. Idk if that was another option or if it was on accident, but I wanted to let you know :)
There fore the answer is...
Hope this helped!
Deforestation is decreasing the forest area and endangering the lives of wild animals. They have no place to hide, no proper lakes or ponds for drinking water, etc. Hence animals die due to dehydration, starvation, and even accidents. So there is a need to conserve trees and forests.
People are using up oil which is a non renewable resource. It will run out at a certain point.
We use too much of some of the land resources that we are running out.