Which planet's axis of rotation lies nearly parallel with the plane of its orbit?

Mercury

Saturn

Earth

Uranus

The invisible line in which the object rotates or spins is called an axis, which runs through its center of mass. Every planet in our solar system rotates on its axis and has their own North and South Poles, where an axis meets the planet's surface.

The Earth's axis is tilted at an angle of 23.5 degrees relative to our orbital plane around the sun. This gives the Earth it's season, depending on the location and the amount of sunshine it receives from the sun.

Just like Earth, Saturn's axis is also tilted at an angle of about 26.7 degree that also gives the planet its season.

Meanwhile Mercury is known to have the smallest tilt compared to any of the planets in our Solar System. It has an angle of about 1/30 degree and because the planet is gravitationally locked with the Sun in a 3:2 spin orbit-resonance, it's rotation is also unique to the Solar System.

On the other hand, of the four planets being considered, Uranus rotates on an axis that is about 98 degrees away from the line perpendicular to its orbit and (only a few degrees out of parallel to its orbit.).