Which of the following is a method suggested by the author to reflect waters value in the

Which of the following is a method suggested by the author to reflect waters value in the last paragraph？

A．People should only be entitled to certain amount of water free.

B．People can borrow water from their neighbors when necessary.

C．People are free to bargain for water in market in their daily lives.

D．People have the right to trade water to raise water productivity.

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