What is the contribution of rivers to drinking water supply?

Correct answer: They can provide water to towns and villages

The direct answer is A: rivers can provide water to towns and villages. Rivers are important freshwater sources, although river water usually needs treatment before it is safe to drink. The reasoning is: rainfall and other sources feed the river; people collect river water; treatment removes or reduces harmful germs, dirt, and some unwanted substances; the treated water is supplied through systems to homes and public places. Option A is correct because rivers can support drinking-water supply in both urban and rural areas. The word “can” is important: not every river is clean or suitable without treatment, and availability may change with season or pollution. Option B is wrong because many communities do obtain drinking water from rivers after suitable purification. Option C is wrong because rivers are generally freshwater systems, not always saline; saltiness is especially associated with seawater, though pollution or local conditions can alter quality. Option D is wrong because rivers carry and supply water rather than making it disappear. Remember: river water may be a source, but purification and safe distribution are necessary before drinking.