The seasons of the Earth are the result of -- a
the tilt of the Earth and its orbit around the Sun.
b
the Sun having a large gravitational pull.
c
the orbit of the moon around the Earth.
d
the continual rotation of the Earth on its tilted axis.

the tilt of the Earth and its orbit around the Sun.

Explanation:

The seasons on the earth is as a result of the tilt of the earth and its orbit around the sun.

These phenomenon causes the four seasons of the earth. The earth is tilted at an angle of 23.5° from the perpendicular.

This causes the differences in yearly exposure of parts of the earth to solar radiation.

At some points, a part can experience very high insolation whereas it is low in other parts.

These variations results in the seasons on the earth.

the answer would be b i believe

a corroding iron, if that's one of your choices