Force is a quantitative measure of the interaction between two bodies. It is a fundamental concept in physics that describes the influence that one body exerts on another, causing it to accelerate or deform. The correct answer is option 'D'.

Explanation:
- Definition of force: A force is defined as a push or pull that can cause an object with mass to change its velocity. It is a vector quantity, which means it has both magnitude and direction. The SI unit of force is the newton (N).
- Interaction between two bodies: When two bodies interact, they exert forces on each other. These forces can be contact forces, such as friction or normal force, or non-contact forces, such as gravitational force or electromagnetic force.
- Quantitative measure: Force is a quantitative measure because it can be measured and expressed numerically. By using appropriate instruments, such as a spring balance or force sensor, the magnitude of a force can be determined. This allows for comparisons and calculations involving forces.
- Newton's second law of motion: The relationship between force, mass, and acceleration is described by Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass (F = ma).
- Calculation of force: In many cases, the force between two bodies can be calculated using the equation F = ma, where F is the force, m is the mass of the object being accelerated, and a is the acceleration produced by the force.
- Examples: For example, when a person pushes a car, the force exerted by the person is measured in newtons. Similarly, when a planet orbits around the sun, the gravitational force between the two bodies can be calculated using Newton's law of universal gravitation.
- Importance of force: Understanding and quantifying forces is essential for many areas of physics and engineering. It allows scientists and engineers to analyze and predict the motion of objects, design structures that can withstand forces, and develop technologies that rely on forces, such as transportation systems or electronic devices.

In conclusion, force is a quantitative measure of the interaction between two bodies. It is expressed numerically and can be calculated using Newton's laws of motion.