The aim of which technique given by F.W. Taylor is to reduce a given line or a product to fixed types, sizes, and characteristics?

The correct option is Standardisation of work.

Let's understand the concept step-by-step to see why this is the correct answer:

1. Understanding F.W. Taylor's Scientific Management:
F.W. Taylor (Frederick Winslow Taylor), known as the Father of Scientific Management, introduced several techniques to improve organizational efficiency, productivity, and streamline manufacturing processes.

2. Analysis of the Techniques:
Let us evaluate the techniques mentioned in the options to see which one aligns with the goal of reducing products to fixed types, sizes, and characteristics:
- Method Study: The aim of method study is to find the "one best way" of doing a job to minimize the cost of production and maximize the utility of resources.
- Time Study: This technique determines the standard time taken to perform a well-defined job, helping to estimate standard labor costs and decide the number of workers required.
- Functional Foremanship: This is a structural technique where Taylor proposed supervising workers through eight specialized foremen to improve the quality of supervision.
- Standardisation (and Simplification) of Work: Standardisation refers to the process of setting standards for every business activity, including process, raw material, time, product, machinery, and working conditions. The specific aim of standardising products is to reduce a given line or product to fixed types, sizes, characteristics, and quality. This helps in ensuring interchangeability of manufactured parts and establishing standards of excellence.

Conclusion:
Therefore, the technique that aims to reduce a product line to fixed types, sizes, and characteristics is indeed Standardisation of work.