To solve the given question, we need to understand Taylor's principle of Scientific Management, specifically the concept of 'Standardization and Simplification'.
According to Taylor's Scientific Management, 'Standardization' refers to the process of establishing norms in processes, products, and management to ensure uniformity and consistency.
'Simplification' in Taylor's context aims to reduce unnecessary diversity, facilitating efficiency by focusing on essential products and processes that improve productivity and reduce costs.
Among the options provided:
Thus, the correct answer is \(\text{Eliminating unnecessary diversity of products}\).
In conclusion, 'Standardization and Simplification' in Taylor's Scientific Management focuses on creating effective and efficient work processes by eliminating variations that do not contribute to productivity.