They where used in the war or they cam from the place they where at war with.
The tools that held by Pharaoh is the crook and the flail.
The crook represents the tools that is used for animal husbandry works that is done by many of the working class in Egypt, and the flail represents the tools that is used for doing agricultural works which is also the backbone of ancient egypt's economy
D. Opportunity cost
Because in the end if you want something you have to work for it, no matter what. Everything generally costs money in this world
The answer is going to be C