A toy manufacturer receives certain components from an overseas supplier and uses them to assemble...

An operational audit would be the most appropriate type of engagement to assess the root causes of the quality issues with components received from an overseas supplier. Operational audits focus on the efficiency and effectiveness of operations, and in this context, would involve examining the processes related to the procurement, inspection, and quality control of components to identify the underlying causes of the quality problems.

IIA Standards: 2210 - Engagement Objectives

IIA Practice Guide: Auditing the Quality Process