Maximum intensity of pressure can be calculated by C/r^2.

Explanation:
To understand why the correct answer is option C, let's break down the equation and understand the variables involved.

Pressure:
Pressure is defined as the force exerted per unit area. Mathematically, it can be expressed as:
Pressure = Force/Area

Intensity of Pressure:
The intensity of pressure refers to the maximum value of pressure at a specific point. It represents the maximum force exerted per unit area at that point.

Variables involved:
- C: Constant value (depends on the situation or problem)
- r: Distance from the point at which pressure is being measured to the source of the force

Explanation of the equation:
The equation C/r^2 represents the intensity of pressure at a point. Let's break it down further:

- C: The constant value (C) represents the magnitude of the force being applied. It can vary depending on the situation or problem being considered. For example, if we are considering a fluid flow problem, C could represent the density of the fluid and the speed of flow.

- r: The variable (r) represents the distance from the point where pressure is being measured to the source of the force. It is important to note that this equation assumes that the force is being applied uniformly in all directions from a single point source. As the distance (r) increases, the intensity of pressure decreases because the force is spread over a larger area.

- r^2: The square of the distance (r^2) is used in the equation to account for the inverse square law. According to the inverse square law, the intensity of a physical quantity (in this case, pressure) decreases with the square of the distance from the source.

Conclusion:
The correct answer to the question is C) C/r^2 because it correctly represents the intensity of pressure at a point. The equation takes into account the magnitude of the force (C) and the distance (r) from the source, following the inverse square law.