Which of the following methods can be used to increase the supply of usable, good-quality water?

Cloud seeding sprays nuclei such as silver iodide into moisture-laden clouds to trigger rainfall and add to the stock of usable freshwater.

Chlorination only disinfects water already in hand by killing germs, improving quality without increasing the quantity supplied.

Metallurgy deals with extracting and shaping metals and has no bearing on water availability.

The claim that none of these can help collapses once a real rain-inducing technique is present.

Seeding is applied over catchments and reservoirs in dry spells to squeeze extra precipitation from clouds.

Rainwater harvesting and desalination are other routes to enlarge the usable water supply.