Answer:
B. acceleration
Step-by-step explanation:
All objects regardless of their mass, shape, and size free fall towards the Earth with the same acceleration in the absence of air resistance.
This phenomenon was studied by the famous physicist Galileo in his Pisa tower experiment.
According to the gravitation force between two bodies, the force experienced by one body due to other is independent of its own mass.
The gravitational force is given by equation
F = GMm/r²
If F is the force acting on the smaller body of mass 'm', then
F = ma
Therefore, the equation becomes,
ma = GMm/r²
a = GM/r²
Here it is clear that the acceleration of the body is independent of its mass or the body itself, because no physical quantity of that body is expressed in that equation.
The acceleration at any point is only the inherent property of the Earth itself.