In human evolution, which characteristic is most closely associated with the development of tool-making?

The development of tool-making in human evolution is most closely associated with increased brain size. This correlation is primarily because larger brains, particularly in the context of the human lineage, have been linked to enhanced cognitive abilities, such as problem-solving, planning, and the ability to manipulate the environment. These cognitive advancements would have enabled early humans to design and create tools that were more effective for tasks such as hunting, gathering, and processing food.

As brain size increased, so did the complexity and sophistication of tools. This relationship underscores the idea that cognitive development was a key factor in the survival and adaptation of early humans, setting them apart in the animal kingdom. The other characteristics listed do not have the same direct relationship with the capacity to make tools as increased brain size does. For instance, while a stronger physical build might assist in using tools more effectively, it does not account for the cognitive processes involved in tool creation. Similarly, the development of less body hair and changes in canine teeth are adaptations that may relate to different aspects of human evolution but are not directly tied to the emergence and advancement of tool-making abilities.