Which of the following is NOT a type of observation technique?

Functional testing is characterized as a technique primarily used in software development and quality assurance to evaluate whether a system or application meets specified requirements. It involves executing a software component or system to ensure that it behaves as expected under various conditions. This is distinctly different from observation techniques, which are primarily focused on watching and interpreting behavior or processes in real-time to gather insights or data.

In contrast, the other options highlight legitimate observation methods. Formal observation involves structured and systematic observation where the observer records specific behaviors or actions. Shadowing is a practice where an observer follows a participant to understand their tasks and processes in a natural setting. Ethnographic study immerses the researcher in the environment being observed to capture a comprehensive understanding of social interactions and cultural contexts. Each of these methods emphasizes the observational gathering of information, particularly in contexts such as business analysis, where understanding stakeholder behavior and processes is essential.