Answer: D. Humans cultivated plants and domesticated animals.
Step-by-step explanation:
The first agricultural revolution took place in prehistoric times, more precisely in the Neolithic period. The man led a nomadic lifestyle before that period; he was constantly on the move because of food search. In the Neolithic, man domesticated the first plant and animal species. The pig and the dog were the first animals, and the cereals the first plants. This encouraged man to form an evening of social community and form permanent settlements because he has had a secure food source ever since.