Which technique is applied to model requirements by identifying parts of a complex business function?

Functional decomposition is the correct technique for modeling requirements by breaking down a complex business function into smaller, more manageable parts. This approach allows business analysts to understand the overall function by dissecting it into its constituent components. Each of these components can then be examined individually, facilitating a clearer understanding of the requirements and how they interrelate.

This technique is particularly useful in requirements analysis because it helps to clarify the functionality that needs to be built or improved, ensuring that nothing is overlooked. By breaking down the business function into discrete elements, stakeholders can more easily engage with and verify the requirements, ultimately leading to a more effective and coherent solution.

Other methods listed, like concept modeling, data dictionaries, and decision modeling, serve distinct purposes within the requirements analysis process. Concept modeling focuses on the relationships and structure of ideas; data dictionaries provide definitions and attributes of data elements; and decision modeling is used to represent business rules and decisions rather than breaking down functions. Each technique has its own specific use case but does not directly address the modeling of complex functions the way functional decomposition does.