Which of the following statements best describes facilitation?
1) An interaction in which the presence of one species alters the environment in a way that diminishes the growth, survival, or reproduction
2) An interaction in which the presence of one species alters the environment in a way that enhances the growth, survival, or reproduction
3) An interaction in which the presence of one species has no effect on the environment or other species
4) An interaction in which the presence of one species alters the environment in a way that is beneficial for some species and harmful for others
