Astudy, generally in the form of an interview or questionnaire, is known as

Usually interviews and questionnaires follow into a type of sampling called "surveys"

The correct answer is a. when they started making tools that will them in cultivating lands, they could raise crops and that made them attached to one place for a longer period of time. after that, they started domesticating animals and building their own permanent settlements that resemble the ones we have today.