A
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
(2021·贵州黔东南苗族侗族自治州高三一模)
Suppose you are hiking with friends in the mountains on a hot summer day and you come to a clean stream.The water in the stream looks so inviting, and you suddenly realize that you’re thirsty.__1__ The answer is as clear as the stream water：don’t drink it! Most mountain freshwater contains tiny living things that you can’t see and isn’t safe to drink, even if it looks pure.
You’ll be safe if you take your own water with you on outdoor adventures.If you can’t carry all the purified water you’ll need, you have some alternatives.__2__ That’s because boiling kills the harmful tiny living things, but it may not remove dangerous chemicals from the water.
__3__ These chemicals make the water safe to drink, but they often give a bad taste.Another method for purifying freshwater is to use filters (过滤器), but experts caution people to choose carefully since not all filters make water absolutely safe to drink.
If you find yourself running out of water, you can preserve your “inner water” by staying out of direct sunlight, covering your skin and wearing a hat, so that you don’t lose too much water through sweating.__4__
In an emergency, if you have to drink untreated water, avoid water that is near shores.Drink from an upstream source of water, if one is available.__5__ If you develop a stomachache a few days later, visit a doctor as soon as possible.
A．What is the safest drinking water?
B．Should you take a drink from the stream?
C．You can boil freshwater to make it safe to drink.
D．You should save freshwater as much as possible.
E．Don’t eat salty food because that will increase your thirst.
F．You can also take along chemicals that kill germs in water.
G．Besides, watch out for shallow water or water that has a bad smell.
【语篇解读】 本文是一篇说明文。文章介绍了在野外处理溪水的办法以及缓解缺水的方法。
1．B 段中题。根据下文“The answer is as clear as the stream water：don’t drink it！(答案就像溪水一样清澈：不要喝它！)”可知，空处是对喝不喝小溪水的疑问句。B选项“Should you take a drink from the stream？(你应该从小溪中喝水吗？)”引起下文。故选B项。
2．C 段中题。根据下文“That’s because boiling kills the harmful tiny living things(那是因为煮沸杀死有害的微小生物)”以及前文“If you can’t carry all the purified water you’ll need, you have some alternatives.(如果你不能携带所有你需要的纯净水，你有一些替代方案。)”可推断，这个替代方案把淡水煮开。C选项“You can boil freshwater to make it safe to drink.”(你可以把淡水煮开，这样就可以安全饮用了。)承上启下。故选C项。
3．F 段首题。根据后文“These chemicals make the water safe to drink(这些化学物质使水可以安全饮用)”可猜测，还有一种方法是用化学物质处理溪水。F选项“You can also take along chemicals that kill germs in water.(你也可以随身携带杀死水中细菌的化学物质。)”引起下文。故选F项。
4．E 段尾题。根据前文“If you find yourself running out of water, you can preserve your ’inner water’ by staying out of direct sunlight, covering your skin and wearing a hat, so that you don’t lose too much water through sweating.(如果你缺水了，你可以通过远离阳光直射、遮住皮肤并戴上帽子来保存体内的水分，这样你就不会在出汗时流失太多的水分。)”可推断本段是讲述如何缓解自己缺水状况的方法。E选项“Don’t eat salty food because that will increase your thirst.(不要吃太咸的食物，那样会使你更口渴。)”承接上文。故选E项。
5．G 段中题。根据上文“In an emergency, if you have to drink untreated water, avoid water that is near shores.Drink from an upstream source of water, if one is available.(在紧急情况下，如果你必须饮用未经处理的水，避免饮用靠近海岸的水。如果有上游的水源，就喝上游的水。)”可推断，本段是在紧急情况下对饮水的要求。G选项“Besides, watch out for shallow water or water that has a bad smell.(此外，要注意浅水或有异味的水。)”与上文有递进关系。故选G项。
