Idk but that it
Just do it
We wouldn’t have the resources we need to get through life such as cooking food, clothing for when we get cold, weapons to protect ourselves, and generally things to keep us alive. If we didn’t have fire we wouldn’t be able to stay warm, and healthy. If we didn’t have weapons like steel, iron, wood, we couldn’t make those things in to self defense mechanisms.
The answer is the first one, you must always cite your sources, even if you have not directly quoted them. It also adds credibility to your work (this is not the only reason, it is merely an incentive)
A because mircobes are used to make Meghane