I believe the answer would be the last option. A resource has value, and people are willing to pay for it most likely because the resource is scarce. When a resource is not enough or the supply is low as compared to its demand, then most likely that price or value of it would increase.
Well, people need food and water to survive, so obviously people are willing to pay for that.
This is apparent in grocery stores, for example. People are willing to pay for the resources in the grocery store- that is, food and water.
Note: Water is just liquid. When I say 'water,' I don't mean ONLY water. I mean all liquids. Its just that all liquids have some percentage of water, so that's why I call it that.
