A one-hectare forest community is sampled in early August. The sample yields 12 small trees, 4 types of vines, as well as 17 native shrubs that represent 10 species. What can be estimated from the sample for the shrubs in the forest community?

A. the forest’s productivity

B. the species richness

C. the degree of forest disturbance

D. the stability of the ecosystem

E. the uniformity of species distribution in the ecosystem