The correct answers are:
4) Logging - Logging, as in most parts of the world is something that destroys the forests, and even if it is regulated properly and new trees are planted when the old ones are taken down, the small trees need much longer period to fully grow and replace the trees that are taken down, while the demand is growing more and more.
7) Pollution - As in most things, the pollution, mainly the soil and water pollution, are directly damaging the forests and contribute to their dying out because of high intake of toxins.
8) Population growth - Because of the ever growing population in the United States and the ever increasing demand for new living facilities, the towns and cities are expanding, and this means clearing the forests as well so that the construction work can take place.
