Which best serves as the title for the passage?

Câu hỏi: Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.
The United Nations recently outlined the extent of the global water crisis, saying that 2.7 billion people would face severe water shortages by 2025 if consumption continues at current rates. Today, an estimated 1.2 billion people drink unclean water, and about 2.5 billion lack proper toilets or waste disposal systems. More than five million people die each year from diseases related to unclean water. Humans are pumping water out of the ground faster than it can be replenished. In this difficult situation, a water conservatiionist, Neil MacLeod in South Africa, has found innovative ways to improve his local water situation.
Neil MacLeod took over as head of Durban Metro Water Services in 1992. The situation he found was a catastrophe. Durban had one million people living in the city and another 1.5 million people who lived in poverty just outside it. The entire city was rife with broken water pipes, leaky toilets, and faulty plumbing whereby 42 percent of the region's water was simply being wasted.
MacLeod's crews began repairing and replacing water pipes. They put water meters on residences, replaced eight-litter toilets with four-litter models, and changed wasteful showers and water taps. To ensure that the poor would receive a basic supply of water, MacLeod installed tanks in homes and apartments to provide 190 liters of water a day free to each household. Water consumption in Durban is now less than it was in 1996, even as 800,000 more people have received service. Through sensible water use, Durban's conservation measures paid for themselves within a year. No new reservoirs will be needed in the coming decades, despite the expected addition of about 300,000 inhabitants.
MacLeod has also turned to water recycling. At the water recycling plant, wastewater is turned into clean water in just 12 hours. Most people are unable to discern a difference between the usual city drinking water and the treated wastewater, although it is actually intended for industrial purposes.
Some people still hope that new technology, such as the desalination of seawater, will solve the world's water problems. ''But the fact is, water conservation is where the big gains are to be made,'' says Sandra Postel of the Global Water Policy Project. The dedication and resourcefulness of people like Neil MacLeod offer inspiration for implementing timely and lasting solutions to the world's water concern.
Which best serves as the title for the passage?
A. South Africa to Succesfully Desalinate Seawater
B. Drinkable Seawater – A Dream Turning Sour?
C. The United Nations to Address Local Water Situations
D. Tackling Water Problems: A Story from South Africa