Directions: There are 2 passages in this section. Each passage is followed by some questionsor unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on Answer Sheet 2 with a single line through the centre. Passage One Questions 46 to 50 are based on the following passage. California has been facing a drought for many years now, with certain areas even having topump freshwater hundreds of miles to their distribution system. The problem is growing asthe population of the state continues to expand. New research has found deep water reservesunder the state which could help solve their drought crisis. Previous drilling of wells could onlyreach depths of 1,000 feet, but due to new pumping practices, water deeper than this can nowbe extracted (抽取). The team at Stanford investigated the aquifers(地下蓄水层)below thisdepth and found that reserves may be triple what was previously thought. It is profitable to drill to depths more than 1,000 feet for oil and gas extraction, but onlyrecently in California has it become profitable to pump water from this depth. The aquifersrange from 1,000 to3,000 feet below the ground, which means that pumping will be expensiveand there are other concerns. The biggest concern of pumping out water from this deep is thegradual setting down of the land surface. As the water is pumped out, the vacant space left iscompacted by the weight of the earth above. Even though pumping from these depths is expensive, it is still cheaper than desalinating()the ocean water in the largely coastal state. Some desalination plants exist where feasible, but they are costly to run and can need constant repairs. Wells are much more reliablesources of freshwater, and California is hoping that these deep wells may be the answer to theirsevere water shortage. One problem with these sources is that the deep water also has a higher level of salt thanshallower aquifers. This means that some wells may even need to undergo desalination afterextraction, thus increasing the cost. Research from the exhaustive study of groundwaterfrom over 950 drilling logs has just been published. New estimates of the water reserves nowgo up to 2,700 billion cubic meters of freshwater.