Which of the following is not one of Kepler's rules for planetary bodies?A. A planet's orbit is an ellipse with the Sun at one of the two center-points.B. A line segment connecting a planet and the sun makes an equal area outside during equal intervals of time.C. The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.D. The orbital period depends on the mass of the planet

• A. D
• B. C
• C. B
• D. A