How many species of fungi can cause fairy rings?

Fairy rings are fascinating circular patterns that appear in grass and other plant materials, and they are associated with the growth of various fungi. The correct answer indicates that around 60 species of fungi are known to cause fairy rings. This number highlights the diversity of fungi involved in this phenomenon, as fairy rings can be formed by different types of fungi, including both mushrooms and other fungal species. These fungi play a significant role in breaking down organic matter in the soil, and their growth patterns can create the distinctive ring shapes that can be observed in landscapes.

The other options suggest a range of species that could possibly be associated with fairy rings but do not accurately represent the current understanding of the diversity of fungi that can lead to the formation of these structures. The number of about 60 species reflects substantial research and observation in the field of mycology, collecting data about the various fungi that have been documented to produce fairy rings.