Which option describes a population? Select one:

A group of birch trees and the soil, water, and air they need.

A single birch tree and all the animals that live on it.

A group of birch trees in an area.

A single birch tree in an area.

How might the effects of el niño impact forests in the united states? a) it could cause hurricanes that would destroy forests in oregon. b) it could cause droughts which would make forest fires more likely. c) it could cause an increase in mold that could kill large amounts of trees. d) it could cause an increase in the length of the wet, rainy seasons in the northwest.