What is the first step in manufacturing where raw materials are processed into a usable form?

The correct answer is the first step in manufacturing where raw materials are processed into a usable form is primary processing. This stage is crucial because it involves transforming raw materials into forms that can be further manufactured into products. For example, it can include activities like milling, smelting, or refining, which are essential for creating the intermediate goods needed in assembly or fabrication processes. By focusing on this initial transformation, primary processing sets the foundation for all subsequent manufacturing steps, ensuring that the raw materials are adequately prepared for more complex production activities.

In contrast, the other selections pertain to different stages of the manufacturing process. Final assembly refers to the phase where the various components and parts come together to form the finished product. Quality control involves inspecting products at various stages to ensure they meet specified standards, and defective inspection focuses on identifying products that do not meet quality criteria. Each of these steps is important but occurs after the primary processing, highlighting the pivotal role this initial stage plays in the entire manufacturing workflow.