Fouling factor is a term used in heat transfer calculations to account for the decrease in heat transfer efficiency due to the presence of fouling deposits on heat transfer surfaces. Fouling refers to the accumulation of unwanted substances, such as scale, corrosion products, or biological matter, on the surfaces of heat exchangers or other heat transfer equipment.

The value of the fouling factor for industrial liquids depends on various factors, including the nature of the liquid, the operating conditions, and the design of the equipment. It is typically determined experimentally and can vary widely for different processes and fluids.

In this case, the given answer is option 'C', which states that the value of the fouling factor for industrial liquids is 0.0002 m2K/W.

The fouling factor is a measure of the resistance to heat transfer caused by fouling deposits. A lower fouling factor indicates less resistance and better heat transfer efficiency. Therefore, option 'C' with a value of 0.0002 m2K/W suggests a lower fouling factor compared to the other options.

It is important to note that the actual fouling factor for a specific industrial liquid in a particular application may differ from the given value. The value provided in the answer is intended to serve as an example or approximation.

In practice, engineers and designers consider various factors when estimating the fouling factor for a specific process. These factors include the type and concentration of contaminants in the liquid, the temperature and pressure conditions, flow rates, and the type of heat transfer surface. Additionally, historical data and experience with similar processes can also be used to estimate the fouling factor.

Overall, the value of the fouling factor for industrial liquids can vary depending on the specific conditions and characteristics of the process. It is important to consider the specific requirements and constraints of each application when estimating the fouling factor to ensure accurate and efficient heat transfer calculations.