Interface analysis is a technique that should be used to analyze input to and output from the product for a large, highly complex project with significant risk. Interface analysis is a technique that involves identifying and specifying how different components of a product interact with each other or with external systems or users. Interface analysis can help to define and document the data flows, formats, protocols, rules, and behaviors of each interface. Interface analysis can also help to identify and mitigate any risks or issues related to compatibility, integration, interoperability, or usability of the product. System analysis is not a technique that should be used to analyze input to and output from the product for a large, highly complex project with significant risk. System analysis is a broad term that refers to various activities and techniques for studying, designing, developing, testing, or maintaining a system. System analysis can include interface analysis as one of its aspects, but it is not a specific technique for analyzing input to and output from the product. Dependency analysis is not a technique that should be used to analyze input to and output from the product for a large, highly complex project with significant risk. Dependency analysis is a technique that involves identifying and evaluating how different elements of a project or a product depend on each other or on external factors. Dependency analysis can help to determine the impact of changes, prioritize tasks, allocate resources, or manage risks. Dependency analysis can include interface analysis as one of its aspects, but it is not a specific technique for analyzing input to and output from the product. Risk analysis is not a technique that should be used to analyze input to and output from the product for a large, highly complex project with significant risk. Risk analysis is a technique that involves identifying and assessing potential threats or uncertainties that may affect a project or a product. Risk analysis can help to quantify or qualify risks, prioritize risks, plan responses, or monitor risks. Risk analysis can include interface analysis as one of its aspects, but it is not a specific technique for analyzing input to and output from the product. References: Business Analysis for Practitioners: A Practice Guide 1, page 78-79; PMI Professional in Business Analysis (PMI-PBA)® Examination Content Outline 2, page 16-17.