What aspect of ergonomics focuses on improving physical interactions between humans and products?

Human factors engineering is the aspect of ergonomics that emphasizes optimizing the interactions between humans and products to enhance comfort, efficiency, and safety. This discipline involves understanding how people use products, considering their physical attributes, cognitive processes, and environmental contexts. By studying these interactions, human factors engineering aims to design products that are intuitive and align with human capabilities and limitations, thereby improving overall user experience and reducing the risk of injury or discomfort.

In contrast, ergonomic testing typically involves evaluating a product for its user-friendliness and comfort, but it doesn't encompass the broader design principles that human factors engineering does. Biomechanics focuses on the mechanical aspects of human movement, which is important but narrower in scope compared to the holistic approach of human factors engineering. Industrial design, while closely related and often incorporating ergonomic principles, primarily concentrates on the aesthetics and functionality of products rather than specifically targeting the physical interactions between users and those products. Thus, human factors engineering is the correct answer as it encompasses a comprehensive understanding of how humans physically interact with products, aiming to enhance those interactions effectively.