Read the following passage  and mark the letter (A, B, C or D) on your answer sheet to indicate the correct answer to each for  the questions. 
            During the late Middle Ages, oil paint took hold as the artistic medium of choice  because it was effective, flexible, and resilient relative to the wax-based, watercolor, fresco, or tempera paints prevalent at the time. Although contemporary commercially prepared paints contain a mixture of pigments and linseed oil, poppy oil paints are also available to connoisseurs. The original recipes developed in medieval European monasteries relies on fast-drying bases derived from various organic oils predominantly valued for their medicinal qualities. The pigments are insoluble, lightproof, and chemically inert powders ground in the base. Occasionally, varnish can be added to increase the paste’s ability to reflect light and to cover pictures with a protective seal. The resulting stiff, resinous compounds are often packaged in flexible metal or plastic tubes. Historically, yellow pigments have been added to the oil, and then the paste was layered over tin foil to imitate the appearance of gold leaf.
            Despite the numerous experiments to accelerate the drying process, oil paints dry comparatively slowly with little color alteration. An important advantage of color stability is that tones and undertones are easy to blend, match, transpose, and grade, and mistakes and smudges are simple to correct. Due to the creamy consistency of most mixtures, artists can exploit their viscosity in thick applications, sprays, thin trickles, and three-dimensional blobs. The purification by boiling and filtering and bleaching of oils can impart varied hues to powdered pigments, while drying time can be reduced by adding metallic oxides. Professional painters who mix their own medium usually have their own trademark methods of mixing materials that art experts recognize as a part of an artist’s creative work.
            The thickness of the paste also plays an important role in defining the stages of painting a picture. After the basic design is sketched in pencil or charcoal, the broad background or foreground areas of the canvas are covered with thin, diluted paint on top of the primer. A thicker paint, often with added varnish, is subsequently used to refine and outline the foundation. The width of the brush depends on the type of paint the artist chooses to use, and stiff bristles are usually found in narrow brushes for making sharp lines, while softer brushes of animal hair can be employed in broad strokes.
The word “viscosity” is closest in meaning to
A.stiffness         
B.elasticity        
C.stickiness       
D.eloquence

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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 from 43 to 50.
Tropical rainforests are being destroyed and badly degraded at an unsustainable rate. Some scientists estimate that in the early 1990s tropical forests were being destroyed at a rate of approximately 28 hectares a minute, or about 14 million hectares each year – an area about the size of the state of Wisconsin. This figure marked a decrease since the 1980s, when approximately 16 million hectares were destroyed each year, largely due to a reported decline of deforestation in the Amazon River Basin in the early 1990s. However, satellite images indicate that rates may have rebounded in the late 1990s as burning in the Amazon increased again. Over the past three decades alone, about 5 million square kilometers – or 20 percent of the world's tropical forests – have been cleared. During this time, deforestation in tropical Asia reached almost 30 percent. High rates of deforestation are inevitably followed by alarming rates of plant and animal extinction because many rainforest species cannot survive outside their pristine rainforest habitat. Some scientists estimate that dozens of rainforest species are becoming extinct every day.
Causes of deforestation vary from location to location, but certain patterns tend to be consistent across all forests. Logging companies in search of valuable rainforest hardwoods, or, less often, oil companies in search of petroleum, are often the first to enter a remote area of rainforest. Some logged forests, if left alone, can regenerate in a few decades. But typically, they are not left alone – the roads built by logging companies often provide access for landless farmers to enter a new area, as well as a means to transport agricultural crops to market. For every 1 kilometer of new roads built through a forested area, 4 to 24 square kilometers are deforested and colonized.
Once the loggers leave the land, a typical cycle of destruction ensues. When the landless farmers arrive, they clear the land for planting. Poor rainforest soils produce a low crop yield, especially after a couple of years. At that point, the farmers often sell their lands to cattle ranchers or large plantation owners. After nutrients have been exhausted and soils compacted by cattle, lands are then abandoned and often laid to waste. Rainforest does not readily regenerate on these lands without human intervention. Meanwhile, the colonist farmers and cattle ranchers move to a new piece of land made accessible by logging roads, where the cycle of deforestation begins again.
(Source: Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation)
Which of the following can result from the loss of tropical rainforests?
A.The disappearance of many rainforest species
B.The decrease in wasted lands
C.The increase in the rainforest habitat
D.The disappearance of landless farmers