Currently? probably overpopulation
The aryans stopped being pastoral nomads and became farmers. The creation of the iron plow and the use of irrigation made it possible for them to turn the jungle along the Ganges river into farmland
Answer:
here are a few topics:
Explanation: first one:
you could talk about the earliest computers invented and how people had to operate them, you could also talk about how computers receive codes and the first ever code created.