Which principle defines the design of products and environments for use by all people without adaptations?

The principle that defines the design of products and environments for use by all people without adaptations is the Principle of Universal Design. This concept emphasizes the creation of products and spaces that are inherently accessible to everyone, regardless of their abilities or disabilities. It aims to ensure that environments are inclusive, allowing maximum usability by the greatest number of individuals without the need for specialized design features or modifications.

Universal Design encompasses several key characteristics, including flexibility in use, simple and intuitive use, perceptible information, tolerance for error, low physical effort, and appropriate size and space for approach and use. By adhering to these guidelines, designers can create functional and accessible spaces that accommodate a wide range of users, ensuring that every individual can participate fully.

This principle is distinct from other options, which may focus on specific aspects of accessibility or usability but do not encompass the comprehensive approach that Universal Design embodies.