Question

a species that has a dramatic positive influence of several other species.

a. touch stone species
b. rosetta stone species
c. keystone species
d. greenhouse species
e. ecological species
f. yellowstone species

Explanation:

A keystone species has a disproportionately large effect on its environment relative to its abundance. It plays a crucial role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community.

Answer:

C. Keystone Species