The correct answer is option 'A', the Gravitational Force.

Gravity is the fundamental force responsible for the motion of celestial bodies and shaping the structure of the universe on a large scale. It is the force of attraction between any two objects with mass, and it plays a crucial role in determining the behavior and interactions of celestial bodies.

Gravity and Celestial Bodies:
- Gravity is the force that keeps celestial bodies, such as stars, planets, moons, asteroids, and comets, in motion around each other. For example, the gravitational force between the Sun and the planets keeps them in their orbits.
- The force of gravity between the Earth and the Moon causes the Moon to revolve around the Earth, resulting in the phenomenon of tides on Earth.
- Gravity also determines the shape and structure of celestial bodies. Under the influence of gravity, massive objects tend to be spherical because the force acts equally from all directions, causing the material to collapse inward toward the center.

Gravity and the Universe:
- On a larger scale, gravity is responsible for the structure and formation of the universe. Gravity acts as the driving force behind the formation of galaxies, galaxy clusters, and other cosmic structures.
- The gravitational force between galaxies causes them to form clusters and superclusters, which are the largest known structures in the universe.
- Gravity also plays a significant role in the expansion of the universe. The mutual gravitational attraction between all matter in the universe causes the expansion to slow down, counteracting the accelerating effect of dark energy.

Key Points:
- The gravitational force is responsible for the motion of celestial bodies and shaping the structure of the universe on a large scale.
- It keeps celestial bodies in motion around each other and determines their orbits.
- Gravity causes the spherical shape of massive objects like stars and planets.
- Gravity is also responsible for the formation of galaxies, galaxy clusters, and the overall structure of the universe.
- The gravitational force between all matter in the universe slows down the expansion of the universe.