Calculate the average rate of change in the sable antelope population between 1992 and 2020. Include the appropriate sign to show whether the population increased or decreased.

Maintaining biodiversity in this reserve is of great importance. The reasons for maintaining biodiversity can be grouped into three main categories: ecological, economic, and aesthetic.

Below are six statements, A to F, regarding the biodiversity of this reserve:

• A: The spectacular landscape and diverse herds of sable antelope and elephants attract photographers and tourists from around the world.
• B: Grazing by large herbivores keeps grass short, preventing catastrophic wildfires and maintaining habitats for smaller insects.
• C: Local communities are employed as rangers and tour guides, which brings income into the local economy.
• D: Controlled harvesting of certain plants provides timber and traditional medicines.
• E: Soil nutrients are recycled more efficiently in areas with a high diversity of native herbivore species.
• F: The presence of rare species inspires local artwork and cultural storytelling.

Complete the classification by matching each of the statements (A to F) with its appropriate category. Each letter may be used once, more than once, or not at all.