Which of the following best describes why objects can stay on the surface of the earth without floating away or being crushed? A.Earth's outer core produces a magnetic field, which keeps objects on the surface of Earth without floating away or being crushed B.Gravity keeps objects on Earth. The mass of Earth gives it a gravitational field that is just right for life on Earth. C.Earth's outer core produces a gravitational field, which keeps objects on the surface of Earth without crushing them. D. Magnesium keeps objects on Earth. The mass of Earth gives it a magnetic field that is just right for life on Earth