Supercharging of the engine is done to increase the power output of the engine. Supercharging is a technique used in internal combustion engines to force more air into the combustion chamber, which allows for more fuel to be burned and ultimately increases the power produced by the engine.

There are several methods of supercharging, but the most common one is the use of a supercharger or a turbocharger. Both of these devices compress the air entering the engine, increasing its density and therefore allowing more oxygen to be present during the combustion process. This results in a more efficient combustion and more power being produced.

Here is a detailed explanation of why supercharging increases the power output of the engine:

1. Increased Air Intake:
- Supercharging increases the amount of air that can be taken into the engine.
- This is achieved by compressing the air or forcing it into the engine at a higher pressure.
- More air means more oxygen available for combustion, which leads to a more powerful combustion process.

2. Increased Fuel Combustion:
- With more air available, the engine can also inject more fuel into the combustion chamber.
- The increased fuel quantity can be burned more efficiently due to the higher oxygen content.
- This results in a more complete combustion, releasing more energy and generating more power.

3. Increased Power Output:
- The combination of increased air intake and increased fuel combustion leads to a higher power output from the engine.
- The additional power can be used to drive the wheels of a vehicle or perform other mechanical work.

It is important to note that supercharging does not increase the space occupied by the engine or the mass of the engine per brake power. These options (B and C) are incorrect because they do not accurately describe the purpose of supercharging. Supercharging is solely aimed at increasing the power output of the engine by increasing the air intake and fuel combustion.