(d) Both (a) Tides and (b) Circular motion of the moon
The gravitational force between the Earth and the moon is responsible for both tides on Earth and the circular motion of the moon around the Earth. The gravitational pull of the moon on Earth's oceans causes the phenomenon of tides, leading to the rise and fall of sea levels. Additionally, the gravitational force between the Earth and the moon is what keeps the moon in orbit around the Earth, resulting in its circular motion.