What general kind of thing is indicated by the nouns fagus and ulmus?

The nouns "fagus" and "ulmus" refer to specific types of trees. "Fagus" denotes the beech tree, while "ulmus" refers to the elm tree. Both of these terms are commonly used in botanical contexts to classify different species within the tree category. Understanding that these terms are linked to trees highlights their significance in environmental systems, ecology, and forestry. Thus, identifying them as representatives of trees makes "C" the appropriate and correct answer.