Answer:
b. the management of limited resources to satisfy unlimited wants.
Step-by-step explanation:
If the resources were unlimited, or the wants were limited, it would be quite possible to satisfy every single need and want in an almost automatic way - there would be no need for economy as such. Unfortunately, that is not the case, so we need to find ways to assign all our limited resources. That's where the government, the markets, the economic agents and the supply and demand step in.
It is in the market where we are able to trade our goods for other goods (e.g.: we trade our money for apples) - we have something, we need another thing, so we trade what we do have for what we don't have.
You cannot ask for a very high price in exchange for your good, because no one would want to buy it from you - they'd rather go see if the competition has a better deal for them.
On the other hand, what if all the sellers agree to sell their goods at a fixed price, or what if somehow one of them becomes the sole owner of the good? The consumer wouldn't have much of a choice, then, so the market would stop being efficient - supply and demand might not be adequately balanced around their equilibrium price. That's were the government and the market regulations come into the picture.
So, as you can see, the fundamental conflict of economics is that there are not enough resources to satisfy all our unlimited wants.