A farmer is reading a nature guide to learn how to make changes to a pond so that it will attract and support wildlife. The guide gives the suggestions listed below.
Help Your Pond Support Wildlife
1. Reduce soil erosion by keeping livestock away from the banks of the pond
2. Allow plants to grow along the shoreline to provide cover, nests, and food for wildlife
3. Float logs near the edge of the water to provide habitats for salamanders
4. Add large rocks to provide sunning sites for turtles

Which suggestion involves interactions between two groups of living organisms?
A. Suggestion 1

B. Suggestion 2

C. Suggestion 3

D. Suggestion 4