Read the following article and answer the question. Article: Desert plants fall into two sorts according to the way they deal with the problem of surviving drought. There are the drought--avoiders--those which persist only as seeds, ready to spring up when it rains, to flower quickly and produce another crop of seeds, and to die again. There are also the drought--resisters--those which have evolved various methods for strong water, locating underground water, or reducing their need for water by such devices as shedding their leaves. The drought--resisters are perennials ,they manage to live from one rainy season to another, slowly growing bigger and bigger. Of these, the succulents is a small but interesting fraction . They may store water in their leaves, in their stems, or in underground containers. In the American deserts the best--known succulents are the cacti . They come in a wide range of sizes, from 50--foot tall giant saguaros to tiny round cacti about the size of a thumb--nail. They take thick, cylindrical or even spherical forms, thereby exposing a minimum of evaporating surface to the air and light. They are leafless, except in youth, and then the leaves are small. Typically their surfaces are spiny, discouraging thirsty animals, and channeled like an accordion , so the fleshy stem may expand quickly when the plant drinks and contract slowly as it uses up the water. The root system is widespread and shallow, with good reason; only about 3 per cent of the rain that falls on the desert penetrates to any significant depth into soil. Question: The passage gives us an impression that _ . Answer:
OPTIONS:
- the desert plants are shaped in a way as if them were designed by somebody on purpose
- more water is needed in desert so that more desert plants can grow there
- more lands will be turned into desert if we do not try harder to save water in our daily life
- the cacti are the most famous desert plants in America

Answer: the desert plants are shaped in a way as if them were designed by somebody on purpose

Read the following article and answer the question. Article: Lots of human foods are dangerous to pets, many of which may seem tasty to our pets but can prove deadly if eaten. It can be very appealing to offer pets food from the table, but pets should not be given human food unless recommended by veterinarians . If you suspect your pet may have eaten a dangerous food, contact veterinarians immediately. In many cases, early recognition and treatment are very important. Chocolate, Coffee, and Caffeine Chocolate contains theobromine, a chemical that is toxic to dogs in large quantities. Chocolate also contains caffeine, which is found in coffee, tea, and certain soft drinks. Different types of chocolate contain different amounts of theobromine and caffeine. For example, dark chocolate and baking chocolate contain more of these compounds than milk chocolate, so a dog would need to eat more milk chocolate to become ill. However, even a few ounces of chocolate can be enough to cause illness in a small dog, so no amount or type of chocolate should be considered "safe" for a dog to eat. Chocolate toxicity can cause vomiting , diarrhea, rapid or irregular heart rate, restlessness, muscle tremors, and seizures. Death can occur within 24 hours of intake. Grapes and Raisins Grapes and raisins can cause sudden kidney failure in .cats and dogs. It is unknown what the toxic agent is in these fruits. However, clinical signs can occur within 24 hours of eating and include vomiting, diarrhea, and tiredness. Other signs of illness relate to the eventual shutdown of kidney functioning. Garlic and Onions Garlic and onions contain chemicals damaging red blood cells in cats and dogs. Affected red blood cells can damage or lose their ability to carry oxygen effectively. Cooking these foods does not reduce their potential toxicity. Fresh, cooked, and/or powdered garlic and/or onions are commonly found in baby food, which is sometimes given to animals when they are sick, so be sure to read food labels carefully. Many cases of human food toxicity in pets are accidental. A pet may find... Question: What effect do chocolate and grapes have in common if eaten by pets? Answer:
OPTIONS:
- They both can cause pets' sudden kidney failure.
- They both contain different amounts of theobromine and caffeine.
- They both can cause pets to vomit.
- They both can cause pets' hearts to beat irregularly.

Answer: They both can cause pets to vomit.

Read the following article and answer the question. Article: The size and location of the world's deserts are always changing. Over millions of years, as climates change and mountains rise, new dry and wet areas appear. But within the last hundred years deserts have been increasing after frightful speed. This is partly because of natural changes, but most responsible for creating deserts are men. Man can make deserts, but they can also prevent them from getting bigger. Algeria is planning a green belt of trees along the edge of the Sahara Desert to stop the sand. In China, too, _ are being built in the northwest to keep the desert from growing. But desert still threaten the world. Experts believe that land that is on the way to becoming deserts equals the size of Australia, Russia and US put together. Can we stop the spread of the world's deserts and save the land that is so essential to mankind? Yes, we can, and we must. Question: The reason for the land that turns into deserts is mostly because of _ Answer:
OPTIONS:
- the changing of the climate
- man
- the natural changes
- the wind

Answer:
man