17. Planets in the solar system are grouped into inner planets and gas planets. What could have caused the formation of land in the inner planets like Mercury, Venus, Mars, and Earth?
A. because the inner planets are close to the sun where high temperatures can condense rock and metal found in these planets.
B. because they often collide with asteroids causing the debris to hit these planets.
C. because the outer planets are too far from the sun they sunlight does not reach them,
D. because the main constitution of the outer planets are gasses that solid materials cannot be formed​