Which planets in the solar system are known to have no moons?

The correct answer is that Mercury and Venus are known to have no moons. This is a notable characteristic of these two inner planets in our solar system.

Mercury, being the closest planet to the Sun, experiences extreme gravitational interactivity with the Sun, which likely prevents it from retaining any satellites. Additionally, its small size and lack of a substantial atmosphere contribute to its inability to capture or maintain moons.

Venus, on the other hand, has a slow rotation and thick atmosphere, which might also hinder moon formation or retention. Both planets are unique in that they have no natural satellites, distinguishing them from other planets, which typically have various numbers of moons.

Other options contain at least one planet that does, in fact, have moons; for example, Earth has one moon and Mars has two. In contrast, Jupiter and Saturn are notable for having many moons, with Jupiter hosting the largest collection in the solar system. Thus, Mercury and Venus stand out for their lack of moons.