The most significant development of hunter-gatherer societies during the Stone Age was Art. This statement is false.
Step-by-step explanation:
The most significant development of hunter-gatherer societies during the Stone Age could be anything ranging from the development of tools to th use of fire on regular basis around the camps of the dwellers and the eating of cooked meat as a result of that.
The most implausible of the statement to be claimed was Art as it is not a stone age discovery in the sense it is to be treated as Art.
Art is a concept that appears in civil societies in its current form and not in the hunter gatherers.