Read the given passage carefully and answer the question that follows

From the seeming irrelevancies of this archaeological gossip, some concrete meaning for the ambiguous term "knowledge" should yet have been emerging. It has at least been distinguished from instinctive "responses" and from what popular psychology terms "memories", as long as such remain personal and private. The knowledge embodied in the hand axes of the Old Stone Age was both useful and public. It enabled our remote precursors or ancestors to make serviceable tools such as they needed to supplement the deficiencies of their limbs and other bodily organs. And it was communicated to and transmitted by all human beings who made hand axes for thousands of generations. Thus this knowledge was preserved - but not only preserved. It was also enriched and extended. During the two or three hundred years over which hand axes were being made, archaeologists can detect improvements in their form and changes in the techniques of manufacture. More efficient tools were produced with less effort. These progressive changes reflect additions to knowledge, discoveries and inventions that were made public and incorporated in the traditional lore or knowledge used, transmitted and maintained by Old Stone Age societies. Of course, the progressive change observed in archaeologists' "hand axes" is just one case of the general technological progress from simple manual tools of stone and bone to complicated machines made of metallic alloys and other artificial substances and operated by electrical or even nuclear power. It is this technological progress that has secured for Homo sapiens the victory over all competitors in the evolutionary race for survival. But technological progress in its turn is just the result and consequence of the accumulation of knowledge. That accumulation was possible just because human knowledge is public; one member of the species can communicate to another what he has found out.