Most people in cities get their water
a. by supplying it themselves
b. by delivery through pipes
c. through private suppliers
d. all of the above

Some of the people can supply themselves with water as well as from private suppliers. But most people in cities get their water by delivery through pipes. This is a common urban way of water supply, that is the cheapest and easiest way to get to the water. This water can be used for bathing, showering, cooking, washing, for almost all needs of urban society. Any alternative way of supply is much more expensive.

The answer is: b.

B- by delivery through pipes

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