The correct answer is: A. Force.
A newton is the unit of force in the International System of Units (SI). It is named after Isaac Newton, the English physicist and mathematician who first described the laws of motion.
One newton is the force required to accelerate a mass of one kilogram at a rate of one metre per second squared.
Momentum is the product of an object’s mass and velocity. It is a vector quantity, meaning that it has both magnitude and direction.
Acceleration due to gravity is the acceleration that an object experiences due to the force of gravity. It is a constant value, equal to 9.80665 m/s^2.
Velocity is the rate of change of an object’s position. It is a vector quantity, meaning that it has both magnitude and direction.
In conclusion, the unit of force is the newton.