"Civilization had been growing gradually along with the cultural and industrial development of Man as homo sapiens for the last 200,000 years. About 40,000-50,000 years ago, humans underwent a very important genetic mutation, when the ........ gene was developed that encodes the dopamine neurotransmitter. It is this neurotransmitter which is responsible for human personality traits (Ding et al). In such a way, humans become more intellectually alert, and as a result develop increasing capacities for leadership and socializing. Fortunately, the climate changes that occurred around 40,000-30,000 BCE helped humans demonstrate their more developed societies, allowing them to migrate across continents and form the beginnings of infrastructure."

Which of the following spaces can come?