Q. Which one of the following is the largest of the inner planets?
Answer: Earth
Notes: The four innermost planets in the Solar System (Mercury, Venus, Earth, and Mars) are sometimes called the "terrestrial" planets because of their proximity to Earth and their similarity as compact solid bodies with rocky surfaces. Earth is the third inner planet and the one we know best. Of the four terrestrial planets, Earth is the largest, and the only one that currently has liquid water, which is necessary for life as we know it.