Answer:
Which statement best identifies one of the central ideas of the text? A. The Earth’s natural elements and distance from the sun allow humans and animals to live successfully on Earth. B. Scientists’ observations of Earth show that the planet may be habitable for humans in the future. C. The Earth’s placement in the universe guarantees that humans will always be able to live comfortably there. D. Scientists’ understanding of Earth’s makeup and movements is still limited, but it is becoming more advanced through satellites.