Answer :
The most accurate addition of "Keystone species" to a concept map would emphasize their role in influencing the diversity of communities by maintaining ecological structures and biodiversity. Thus, the correct answer is option A.
When adding "Keystone species" to a concept map, the most accurate answer to the question would be: a. Keystone species influence the diversity of communities. This is because they play a critical role in maintaining the structure of ecological communities and biodiversity.
For example, the intertidal sea star Pisaster ochraceus is a keystone species; its removal leads to an increase in mussel populations, which in turn significantly alters the species composition and reduces biodiversity. Another example is the banded tetra, which supplies almost all of the phosphorus necessary for the ecosystem, impacting various species within the community and its biodiversity.