HELP PLZ !!! What is the role of a keystone species? Limiting the abundance of a competitively dominant species
Populating the ecosystem to decrease diversity
Exploiting the key resources in an ecosystem
Competitively dominant to other organisms in the ecosystem

i do not know and i have a 100 in this class

true                                                                                                       true true true true true true

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.