Which of the following planets is known for its rusty color due to iron oxide?

Mars is known for its distinctive rusty color, which is a result of iron oxide, commonly known as rust, covering its surface. This phenomenon gives Mars a reddish appearance when viewed from space or from Earth, earning it the nickname "The Red Planet." The presence of iron oxide is a key characteristic of Mars's surface chemistry and geology, reflecting its history of volcanic activity and the past presence of water.

The other planets mentioned do not have the same reddish hue associated with iron oxide. Earth, while it has iron in its composition, is primarily covered by oceans and vegetation, leading to a diverse color palette of blues and greens. Venus, with its thick atmosphere and clouds of sulfuric acid, appears predominantly yellowish-white due to the reflection of sunlight off its clouds. Mercury, being a small, rocky planet similar to the Moon, features a grayish surface marked by craters but does not exhibit the rusty coloration characteristic of Mars.