Fortunately, there are substitutes for sand: asphalt and concrete can be recycled, houses can be built with straw and wood, and mud can be used for reclamation. In rich countries, government policy will encourage a shift towards such substitutes. In poorer countries, too, builders are likely to shift away from sand as ____ price rises. However, unless law enforcement improves, that will be a very slow process. Which choice completes the text so that it conforms to the conventions of Standard English? (1 Point) its their it's one's