What ability represents a key advancement in early human evolution, allowing for design rather than trial and error in tool-making?

The key advancement in early human evolution that facilitated design rather than trial and error in tool-making is symbolic thinking. This ability allowed early humans to conceptualize ideas and represent them mentally before creating physical tools. Symbolic thinking encompasses the use of symbols and abstract concepts, enabling individuals to plan and design tools purposefully.

With symbolic thinking, early humans could visualize the functions of their tools and refine their designs based on past experiences. This cognitive leap meant they could innovate and improve upon existing technologies, leading to more effective and specialized tools for various tasks. In contrast, the other options, such as art, social organization, and language development, although significant in human development, do not specifically pertain to the advancement in cognitive ability that drives intentional design in tool-making.