Which planet in the solar system has a natural satellite having its own atmosphere?
A) Mercury
B) Saturn
C) Earth
D) Uranus

Hint: Let us discuss satellites in brief; a satellite is a body that revolves around an object of heavier mass. A natural satellite can thus be defined as a heavenly body in space that orbits around a bigger body. Natural satellites are generally referred to as moons because the moon is a natural satellite of the earth.

Complete step by step solution:
Titan is the largest moon of Saturn and also the second-largest natural satellite within our solar system. It is the second-largest moon after Jupiter's moon Ganymede and is larger than Mercury. It is the sole moon known to possess a dense atmosphere, and therefore the only known body in our solar system, aside from Earth, where clear evidence of stable bodies having surface liquid has been found.

The atmosphere of Titan is essentially made up of nitrogen, with minor components leading to the formation of methane and ethane clouds and heavy organ nitrogen haze. The climate includes wind and rain and leads to the creation of surface features like those found on Earth, namely dunes, rivers, lakes, seas (probably of liquid methane and ethane), and deltas. As on Earth, the climate on Titan is dominated by seasonal weather patterns. With its surface and subsurface liquids and robust nitrogen atmosphere, Titan's methane cycle is similar to Earth's water cycle in many ways. Titan's atmosphere is twice as thick as Earth's, making it difficult for astronomical instruments to image its surface.

Hence Saturn is a natural satellite having its own atmosphere. So, option (B) is the correct answer.

Note: Galileo was among the first people to realize that other planets can have moons. With his newly invented telescope, Galileo was able to discover the four moons of Jupiter. At first, he thought they were stars, but then he noticed that every night, the four points of starlight seemed to change positions slightly. He later realized that they were moons orbiting around Jupiter.