The correct option is B All
The period before the discovery of the art of writing is called the Prehistoric age. This is so because we do not find evidence of the linguistic development or the use of scripts. In this age, man was a nomad and indulged in hunting and food-gathering. Archaeologists have discovered few tools created and used by these people. Probably they used tools made of stone, wood and bones. Among these, only tools made of stone have survived today, providing us the sources for study.