Which of the following best explains why the biosphere is a key component of the earth’s systems? a. the biosphere is a key component of the earth’s systems because it is a common concept to many disciplines in science. b. the biosphere is a key component of the earth’s systems because the seasonal cycles directly affect primary productivity. c. the biosphere is a key component of the earth’s systems because it drive the other systems by interacting with and exchanging matter and energy with the other spheres. d. the biosphere is a key component of the earth’s systems because it has evolved to create the chemical composition of the planet we know today.